Help?

Jess
I was 15 and had sex. My boyfriend at the time got me high and we went back to his house and he was all over me. He kept asking me to have sex I kept saying no. He kept pushing it and pushing it until I finally said yes just to shut him up. So we did it. I regret it so much and wanted to know if that is considered rape. I never thought about it until now and now I want to know people's opinions. I'm 18 now and because of that I let guys have sex with me just so I can get it out of my head. Until I found a guy that I'm currently with that doesn't pressure me into it and I feel safe. But anyways, does that consider to be rape even if I said yes because he wouldn't stop pressuring me? Please respond.