Bleeding every time we have sex

I had a 30 day period (saw the doctor and they’re doing bloodwork but hasn’t come back yet) and that ended about a week ago. I’ve had sex 3 days in a row and about halfway through the sex I start to bleed a lot. I’m so worried/confused about what’s going on. Has anyone experienced this? I’ve been with my husband for years and have never had an STD neither has he so that’s not it. He’s not abnormally large either because I’m sure someone might ask that. We haven’t changed positions or done anything different. I’m worried about it, especially after bleeding for 30 days.