sex hurts!!!!

So... three years ago, when I was 18 I'd had sex for the first time. It didn't take long because I told him to stop because it was hurting as hell. We did try again but again I told him to stop. Three years later, like last month I did it with my “friend” twice and it did hurt as well, not like the first time but yeah, both times. Today I tried again with my newbie, and it did hurt agaiiiin. I've never experienced that good sensation you guys have. Is it something wrong with me? Or it's because I do it and stop and wait too long to do it again? I'm frustrated, I don't want to feel pain anymore. Help pleaseee. Do I have to see a doctor? Or my vagina is way too small to handle a penis? (Joking😂😂😂)