What Causes Discharge Of Blood Clots And White Discharge With Red Veins?

last night my boyfriend and I had unprotected sex and he didn't pull out. I have my period and it was light I have been on birth control for the last 6 weeks. Today I went to the bathroom (use tampons) and on the tampon was a red blood clots and something similar that was kind of whitish with red veins on it. Then I wiped and had another red clot and the other clot also. What could this be?