Hey There.
Possibly if your age is correct - then yes I would personally be slightly worried.
It might be a good idea to talk to a professional as we can only give opinions on here.
How do you feel about what your friends have been saying? Why rush into these things at such an early age? Were they different guys?
If you could answer these, I'd be able to give you more of a specific answer. Have a look around this site though, there have been many other threads similar to this one - I'll post a few links :]
http://www.teenhelp.org/forums/f124-...ddiction-what/
http://www.teenhelp.org/forums/f124-...even-possible/
Also use Google to read about other peoples stories, take a look on the BBC Health Section, and Health Services and sites like that.
At your age, it does seem a little strange for you to have so many sexual experiences, and it wouldn't hurt if you cut down a little bit. Please, Please, also make sure that you are using protection - you don't want any nasty infections =]
I hope this helps, feel free to
PM or email me.
Take Care,
Claire x
[EDIT]:: Also check out the thread below