Weird bleeding

Tuesday-Wednesday I had rougher sex I had some cramping afterwards which is pretty normal for me, but it still hasn’t gone away. Thursday o started bleeding when I pee, I thought it was my period and when I put a tampon on it was full after about 6 hours. After that I took it out and had no blood on my underwear. When I go pee the toilet bowl is full of blood. The cramping is on my lower stomach and around my lower back almost feels like a pulled muscle, not oeriod cramps. What could this be!?