I bled last night. Plz help

Hello all. I am 13 weeks pregnant. Everything was fine as per doctor visit last month. Last night i had intercourse with husband and after that when i was cleaning myself i found out that i am bleeding. It wad dark red blood upon wiping. It was a fearful night. Couldnt slept properly. And now next day the blood has turned into brown streaky discharge. Its dark brown in color just like we have at the last day of period. I have slight pelvic cramps as well. I am scared. Is this normal to bleed after sex while pregnant? Or this is a sign of miscarriage. Please help.