I need help

My period is 3 days late and I really truly think I’m pregnant. I’m only 15, my birthday’s in January. I have so many plans for my life and I don’t want to not fulfill my potential. I’ve only been w my bf for 4 months and he doesn’t think I should keep it if I’m pregnant. I know it would be so incredibly dumb to keep it but I don’t think I could have an abortion. I don’t know how I’d tell my family. I think that if I were pregnant, I’d think ab home abortifacents. I know that keeping it would ruin my relationship bc he wouldnt be happy with having a kid, and if I didn’t have it I’d end up resenting him bc I’d feel like he took it away from me. I know that I’m young and my relationship, statistically, wouldn’t last. But, it’s so healthy and we love eachother so much. I know how it looks, but that’s not how it is. Please give me advice. I just wanna know what’s best in case I am really pregnant.