Q Doc, I am a young woman and I have missed a period. I am worried I am pregnant! I really hope I'm not.

My partner and I used a condom, but I am wondering if it could have had a hole in it.

I did a pregnancy test, and this was negative, but could it have been wrong?

A Today's pregnancy tests are very accurate, provided you carry them out in strict accordance with the instructions in the pack. That makes it very unlikely that you are pregnant.

However, just in case you did the test wrong, I suggest you do another one right away. If that is negative, you have nothing to fret about.

So why have you missed your menses? Common causes in your age group are anaemia and emotional stress. Also, some girls who do a lot of athletic training lose their periods for a while.

Once you have done the 'repeat test', you should visit a doc for a full check-up. I am sure she will be able to discover whether you are anaemic, or whether there is any other reason for the absence of your menses. Good luck.

Q I am an 18-year-old man who was seduced by an older woman a few years ago. Since then, I have not had sex.

But I often find that I have 'leaked' something white on to the inside of my pants. I have checked out the Internet and it seems this could be due to gonorrhoea.

Do you think I got the disease from that girl?

A I really don't think you have gonorrhoea ('the clap') at all. That infection gives males intense pain while passing urine - like passing red-hot razor blades. You don't have that symptom. It also causes a discharge from the penis, but this is not usually like the white fluid you have seen on your pants.

My guess is that you are just seeing a little dried seminal fluid (semen) on your underwear. That is completely normal for your age.

However, I do think that you should have a check-up from a doc.

Q I am a 19-year-old university student and I had a baby last year. I didn't want to get pregnant again, so recently I opted to take the contraceptive injection. I understand it lasts three months.

But a few weeks ago, I noticed I was bleeding vaginally. I thought this was probably caused by rough sex. However, the bleeding has continued. So I am wondering if the contraceptive jab is actually working? Could I be pregnant?

A It is most unlikely that you are pregnant. As you say, the jab lasts three months and it is very nearly 100 per cent effective.

But what a lot of women do not realise is that the main side effect of 'the shot' is that the periods may become highly irregular. More than 40 per cent of women who take the jab do get some derangement of the menses. Two things can happen:

The menses can disappear altogether for a while.

They can become much too frequent.

Clearly, the latter has happened to you. It is unfortunate that you did not realise that this side effect of the shot could occur. However, I do assure you that this is no big deal, even though it is a nuisance for you.

The bleeding will eventually stop, but I think that you should see a doc. He or she may give you hormone tablets to put an end to the blood loss.

Q I am a 17-year-old guy. I am astonished by this, but an older couple, who I think are in their 30s or 40s, have invited me to join them in bed next week. The woman is still very attractive.

They seem to be fascinated by the fact that I am a virgin. Should I go ahead?

A I really do NOT think you should do this. It is quite common for more mature couples to invite a 'toy boy' to join them in their lovemaking. However, I have seen it lead to trouble in the past, because powerful emotions, such as jealousy, may be aroused.

Also, if this couple has a swinging sex life, they might give you a sexually transmitted infection. My advice: Stay away.

Q I am a female teenager. Something has happened to me, and I would like you to explain it.

I have to tell you that I am sexually active. I know you may disapprove of this. On the last occasion when I had sex, my partner noticed that I was bleeding. Most naturally, I cried because I did not know what was happening.

I went into the shower and tried to stop it, but I couldn't for a long time. I felt weak and I also felt a bit of pain.

I know that having sex at my age is not acceptable, but I would like to be given the medical facts, as well as advice on what has happened to me and what I should do in the future.

A It seems like you were NOT a virgin when this bleeding occurred. So, presumably, the blood loss was NOT due to the breaking of your hymen.

When a young woman suddenly starts bleeding during sex, the usual explanation is that she has sustained a cut inside the vagina. Very often, this is caused by her partner's fingernail. That is particularly likely if the man is inexperienced at lovemaking.

So, the odds are that your partner accidentally cut you inside your vagina. Such cuts do heal up, but that generally takes several weeks.

Having sex may open up the cut again, if it has not fully healed. In fact, I am doubtful if you should be having sex at all, as you seem to be pretty young.

I suggest that you see a doctor and have an internal check-up. She can confirm whether there is a cut and whether it has healed. Also, she can advise you about your future sex life. I wish you well.

Q I am a 16-year-old girl and for the last three years I've had a major crush on a guy in his mid-30s.

I think about him constantly. When I see him, I get so nervous and sweaty. I even cried when I saw him with somebody else.

What can I do?

A I am afraid that the odds against you being able to form a relationship with a guy who is so much older than you are enormous. You are experiencing a lot of pain and I urge you to have a few sessions with an experienced counsellor who can help you work through these feelings. You WILL come out on the other side!

Email questions to saturdaylife@gleanerjm.com or post to Doctor's Advice, c/o The Gleaner Company, 7 North Street, Kingston.