He’s soft/:

I know this might be TMI but I don’t know what to think.! I’ve been with my boyfriend for awhile now and not too long ago we started having sex. The point is , he never finishes and before you know it he goes soft! I don’t know if it’s me or him? He’s told me that it’s never happened to him before and I’m the first girl it has ever happened to? He tells me it’s cause he’s still shy around me but I don’t know/:!! Am I the problem?