pregnancy tips?

Hello, I tried posting before so this might be the same post. my bad…. okay my question is, is that I am trying to get pregnant with one of my friends. He is basically a "sperm donnor". He’s willing to be a father and to love the child, but he understands that I would be the "parent" I had sex with him a week ago and the day after I had sex with him I started having cramps, feeling ill, my breasts started hurting, I ate and drank like crazy. It was weird the day after so I think it might just be my head. Im having cramps and Im scared that I am not pregnant. My friend and I only want to have sex as much as needed. We dont want to be sex buddies or anything. So having sex as much as possible is not possible. I had a miscarrage a few years ago so Im scared that I’ll have another miscarrage. I also am still irregular so the whole having sex on your whatever day doesnt work for me. Can anyone help me? I hope to hear back from someone soon.
Best regards
Katie