Messed up in Sex twice , possibly losing intimacy

I (23M) and my boyfriend (21FtM) have loved each other for almost a good year now. We live in separate states pretty far apart. There was a lot of back and forth between us but it was mostly my fault for being such a paranoid person. Things got resolved and I met him again a few days ago. We went on dates and we were having fun with each other.

We got aroused at each other and did the deed. Unfortunately, there were a lot of mistakes made. So many mistakes that he told me straight up either I fixed it or he might look for other people and he wanted to keep it monogamous. I'm at a situation where if I don't get better at it I might lose him. I don't want to lose him. I've been practicing (alone ofc) and have been improving but it's up to no avail that I can do it. I heard it was probably due to anxiety, which seems plausible. But he doesn't see me as sexually intimate anymore and I feel like I'm nothing to him. He's scared that I might fuck up again and I'm being confident. At this point, I'm just going to buy some pills or something but it hurts when the one person you love and make a connection with says he might look for other people if I don't get this right.

I feel like I'm nothing to him.

EDIT: Just want to say thank you for the inputs and I've been a bit vague about it so let me clear it up.

Most of my mistakes were not being able to keep the erection up and finding the right spots , especially cause he's literally 5 feet.

We talked last night about it and it's been alot better and he's extremely sorry about himself being mean to me about it and should be helping me instead of put blame onto me over and over. He would even buy me a toy for it to practice instead of just ya know, using my hands, so when the next time we meet it's alot better.

He won't be putting pressure onto me anymore so I won't be given a giant ultimatum of fight or flight.