My question is y r my breasts tender they never r like that on my period an my period just ended my boyfriend came in me on my period could i be prego?

Highly unlikely: To be pregnant since just had period. May be hormonal or ma be from high caffeine intake.

Yes: Anytime you have unprotected sex there is a chance of becoming pregnant. It is less likely if you were menstruating. The best thing to do is to take a pregnancy test. Many tests can detect pregnancy several days before your missed period.