Advice SOMEONE HELP

Okay so me and my boyfriend for our first time we tried having sex we did for about three seconds and my boyfriend was so nervous he lost his boner... then we tried again and the same thing happened. i asked him if it was me he said no he said “i lost my boner the first time and im worried it’s going to happened again so that’s why”.

how do i help him get through this i keep thinking it’s my fault 😭😭😭 someone help and it’s also very frustrating because i’ve tried everything and we love each other very much and i think it’s me?