Okay I am 15 and yesterday my boyfriend wanted me to meet him up and go have fun so I did. After a while he wanted me to suck his dick so I did and after I realized I swallowed some sperm. Is that okay or will something happen???
You can get a lot of information about oral sex from Scarleteen's Mouthing Off on Oral Sex page. As far as whether it's ok and if something will happen the good news is you don't have to worry about getting pregnant. But! Swallowing some of his sperm means that he wasn't wearing a condom and that means that if he has any sexually or even just socially transmitted disease you weren't protected.
Even if you're oh-so-very-sure you and your partner are safe, unless you've been together six months or more with no other partners, and have both tested negatively for at least that amount of time twice, chances are, you're taking a risk. Unprotected oral sex is considered by sex experts to be a high-to-moderate risk behavior when it comes to STIs (and the risks are higher with fellatio than with cunnilingus). If the situation is such that you have taken all of those precautions for that period of time, your risk of STIs via oral sex is far lower. So long as there are no STIs present, "swallowing" semen or female vaginal fluids cannot make you ill and does not pose other risks.
Bottom line is that you maybe want to be a little more careful if you haven't been partners for long.