Every now and then i bleed after sex. i heard that if you rarely bleed after sex it can be a sign of vaginal or cervical cancer?

Yes: Best to have it checked by your gyn. Bleeding after intercourse may be a sign of gyn cancer.

Bleeding with sex: Bleeding after sexual intercourse, is a sign of cervical cancer; however, cervical cancer in your age group is extremely rare. It is doubtful that you have cervical cancer because if your age, but you need to see your gynecologist.