Out of the 30 times we've had sex this month, I've only came once

So I have an issue that has never been more apparent to me than now- my boy friend only last 1 minute in bed at the MOST. Its getting to the point where i dont even wanna have sex anymore because its absolutely pointless. We run all the stops, get each other turned on then bam, were done. It NEVER used to be this way. Sometimes we would have sex until the morning came up, i have no clue what happened. I hope i dont sound like an asshole, but it makes me so mad because he acts like theres nothing wrong and 30 second sex is totally fine. Im kind of insecure, so it makes me think, do i not turn him on enough?? How do i even bring up a topic like this without hurting his ego???