What should I do? (Oral)

Idk what to do, I will spend a long ass time giving my bf head, I'll do it until he cums but he rarely goes down on me and when he does he never makes me finish. He'll be going down on me for at most 40 minutes and then he'll just stop and say, I suck at this I'm sorry and then he'll just go on about his day, and I won't get to finish. It is me bc I take to long? How do I go about talking to him about this so I can finish too bc I want to CUM!!.