What Causes Bleeding After Intercourse?

i had was super saturated thursday and friday like i was ovulating and i seen my boyfriend saturday we had intercourse and i started bleeding. SUNDAY i kept on bleeding but not heavy so i assumed that was my cycle well Monday came and there was so saturation on my pad and tuesday i had a couple of small clots and the blood turned brown Wed it was brown and stopped. I have been having this issue of bleeding after intercourse but i want to know could be pregnant