Bleeding 5 days after af ends ??????

Just curious if anyone has experienced this before. Period came and gone like normal. About 5 days after we have sex. Nothing too rough. I had a hard time orgasming. Like I had 2 but they were very very small. That's kinda weird for me. Well when we finished I got up and looked at his dick and it had a lot of bright red blood on it. I go pee and wash up and there's like a bun h of blood on it. Bright red blood. I clean up and lay back in the bed and then about an hour later I go check again only this time same amount of blood but I had a blood clot with it about the size of a nickle. I have been spotting ever since then and it's brown now. Does anyone know what's going on ? Also I have been cramping since period has ended and still cramping.