Boyfriend takes forever?

So my boyfriend and I have sex fairly often and he takes a very long time to ejaculate. Am I doing something wrong? The "fastest" it's ever been was 55 minutes! I try to mix it up with giving him head and having sex and such but it still doesn't get the job done any time quickly. I'm just really nervous I'm doing something wrong! He tells me it's great all the time and I'm doing it all correctly and well, but I still can't help but think I'm terrible in bed. Maybe I don't turn him on enough? (Please be kind in comments!)