You've hit puberty and your hormones are probably raging. There's more to puberty than the curse, you know. Boys' hormones are raging even more than yours, with an added peer-pressure to score. Add to that the influence of Britany Spears, Victoria Secret TV commercials, not to mention the totally dumb Cialis ad and you are totally into the experience.
But the DOUBLE STANDARD for women requires that you just say no, and your parents and the government expect you to be celibate even though they weren't when they were your age. Consequently, you are deprived of information and real facts of preventing disease and pregnancy.
Don't let them scare you. Sex is fun and can be enjoyed with few consequences if you know the real facts and don't mistake sex for love or committment.
Get wise, sister.
If the boy is that hot to score and you are comfortable with him, make him buy or steal condoms first. Watch him put it on properly and remove it when you're done. A fresh condom every time. Bare back is just stupid and you will bear the consequences, not him. If he is too stupid, cheap, or lazy to provide condoms, find someone else.
Orgasm! The whole point. It may take you longer than it takes your partner, but if he finishes before you have yours, dump him. If he doesn't know that you need it too, explain to him to try again.
Older men: They may know about how to give great sex, but an older man who risks jail time for statutory rape obviously has some problems that you don't want to get involved in.
Reasons 1 through 3 are not real reasons. They just switch responsibility for your life to someone else and you are still not free. You'll probably be divorced and a single mother in 3-5 years with no experience in taking care of yourself, much less of your children.
I hope this helps you some. Society is depriving you of information that affects your life and your future. Don't fall into the trap. But if you let it happen, it's your own fault and you have no right to whine about it.