how do I make him feel better? 😓

So my boyfriend was going down on me last night and for some reason he couldn't make me cum. That resulted in him being very upset. He was saying that he failed and he wasn't fully satisfied with his performance. He is the type of guy that likes to take care of me before I take care of him or even begin to touch him and he will not give up until I'm good (I love that). I repeatedly told him that it was all okay because he is usually very good at getting me to orgasm but that he won't always get it right. What can I do to make him feel better? Can I even make him feel better?