Cumming to Fast

Stephanie
What can I do to make my boyfriend feel better when he's upset about cumming too fast. We have sex plenty when we see each other but yesterday he came to fast on like the 4th round, which made him upset. Frankly it doesn't make me upset when he cums quicker because I feel like it's not that bad, and there will always be a next round, but he got very upset saying sorry many times. I tell him it doesn't matter and that I don't care and that it happens but he's touchy about it. Idk what else to tell him..