Only during intercourse especially doing it in one position my perineum get paper cut like tear. can this be herpes?

Possibly: This problem mandates a real-time (face-to-face) meeting with a doctor. A history has to be taken along with a examination as well as labs and other tests. Only after all this will your doctor be in a position to tell you what's wrong and what needs to be done to help you.

See an OB/GYN: Without an exam would only be guessing and that is not what you need. If this is happening in only one sexual position there may be an anatomical problem. Herpes is not likely to appear in this manner. Go get examined.