I have my menstruation april 8 to 11 i had sex april 12 to 17 is there a posibility that i am pregnant?

Yes, it's possible: A fertile young woman having sex... Always a possibility of getting pregnant. If the period started april 8, with 28-day cycles, ovulation would be around april 22. That means the possibility of pregnancy would be higher if there is early ovulation this cycle, or if cycles are usually shorter than 28 days.

Always: There is always a possibility of pregnancy if you had unprotected sex. It is unlikely in this case that you were fertile during this time so you might be lucky this time. You ovulate 14 days before your period starts. So, depending on the time between when the next one is due, count backwards14 days from yor next due date. That is when you will ovulate&are fertile about 3 days then.