This is an HIV specific forum, plus your information is incorrect I know a lot of teenager that are HIV positive.
You'll be ok. The morning after pill will most defenitely prevent you from getting pregnant. My wife has take it a couple of times and it worked like a bomb. Him being sick, infected with a std is a long shot.. unless he had sex with multiple risky/suspicious partners, I won't be worried. I mean you guys are still teens, it's not like you guys have active sexual lives with multiple partners.
Need to know what exactly you are looking for. HIV question? Pregnancy question?
In sick do you mean if he has a STD or HIV?