Confused on what happened after sex

I recently started talking to this guy we went to hs together lost touch and rekindled this summer. We have agreed to be FWB and he talks about what he wants to do sexually when we meet( dirty talking).

The first time we hooked up he couldn’t perform and I let it go and was not upset he was very apologetic. He has talked about hooking up again and what he wants to do when we meet (sexually)but every time I ask to chill he always has an excuse I live on campus (far from home )so often time it’s hard. Should I ask him more on what’s going or should I just believe our schedule is very different?