My 20 minute breakup

So me and my boyfriend have been dating for almost 6 months. He was over at my house on Thursday and we were fine, we watched movies, fooled around, we were just in each others company and loving it. Until we got in a small fight. He told me he says nothing he does is good enough and i tried to explain to him how much he means to me and i love everything he does for me. Then we made up and we were fine. Until he saw messages between me and an old friend and she was just asking questions about our relationship and she asked if i were in love with him and do i see myself being in love with him. I was truthful with her and told her no a the moment i’m not in love with him and as of right now i don’t see that happening for a long time. He saw those messages and he started asking questions like do i see a future with him and i do and he said he wasn’t sure if he could and he ended up breaking up with me and i was trying to be supportive about it cause i actually understood his reasons. After that he left but i called him to come back because i had recently went on vacation and i got him a gift and i told him if he wants it he has to come and get it cause i have no use for it. So when he came back we talked and i told him i take everything back i said. I told him i can’t support the breakup and that i wanted to be with him and i wanted to make it work and he thought about it as we were standing outside my house and agreed. He said he thinks we can make it work and we ended u getting back together. But in those 20 minutes that we were broken up i was crushed. And now every time he takes too long to respond or acts a little weird i get nervous that he’s thinking too much and takes back what he said even though eh keeps telling me he’s happy we got back together and he’s sorry for what he put me through. But it’s only been a few days and i still get nervous and i don’t know what to do to know for sure that we are completely okay and that he won’t change his mind again.