Bleeding during sex

So I have noticed something after recently spending the night with someone. I have noticed that when I go through periods of time where I am not consistently having sex, I bleed. The other night was the first time I had sex in a little over a month, and it hurt really bad almost the whole time until I went on top and didn’t go all the way down. Once we turned on the lights there was blood all over the condom and my legs. I got completely tested for STI/STDs before the last person I had sex with, came back completely clean, and have been using condoms since so I’m confident that its not an infection/disease. It has been 24 hours and I’m not sore but my abdomen/pelvic area still has a faint discomfort/pain feeling. Is this normal for some people?