My boyfriend can only get hard once a day and after we have sex he can't have it again that day. Normal?

My boyfriend and I have been having sex for awhile now. After we have sex once he can't get hard again even if i wait hours. I feel really self conscious about it because sometimes I feel like it is my fault. Also, most of the time when we do have sex I don't even find it pleasurable. I feel like he only cares about himself being satisfied. Please help!