Pain during sex

So I had sex w my boyfriend Wednesday and it was really painful, felt like the first time I ever had sex, I was bleeding and my vagina burned when I peed after sex. The next morning I was better and we had sex again and it was for a long time like two hours, my vagina was burning and it burned when I peed. Today, Friday, I keep on bleeding and I believe it’s period blood? But when I was wiping a spot of blood came out and I thought it was like just blood spotting. But as I look close I decided to touch it and it was my skin! I freaked out. I don’t know what to do. My skin maybe rubbed off while having sex? Not sure if I should go to the doctor