im 15 years old and about 17weeks pregnant.. id had been fainting and i didnt know i was pregnant... it always seemed to happen 1-2 days after id had sex. even now i know im pregnant and im looking after myself properly i still faint after sex... does anyone have any idea or know why i faint? or even what i should do?

So it doesn't happen right after sex but a couple of days after?

Hey,
You should probably talk to your doctor at your next visit. My doctor told me to stay away from "excessive heat", and your body heat plus your partners can just be over heating you. Which in turns makes you black out or faint. Maybe, you could keep a fan on, open a window, drink some orange juice quick after, or even some water. Lol. You should also be drinking alot of water. If you don't consume enough H20 then you are more likely to faint, because your body is dehydrated.
And you should ask your DR if its normal or not. That is the best advice I can give you, when it doubt...as the doctor.

yeah... only ever about 1-2 days after... never a few minutes after or anything.. just always 1-2 days after...

It may be your body catching up to you with exhaustion. I get dizzy after sex, but never faint... I would definately discuss this with your doctor.

Ok, that's kind of odd... I think that you should probably go to the doctor to find out if something else is wrong. Let us know, ok?
Also make sure that you keep hydrated and that you have some electrolytes (some water is electrolyte enhanced).