My boyfriend says he wishes my butt was a little bigger!?!

So I was talking to my boyfriend and he asked me how much I weight, I said 150 and he's like that's perfect that he likes me like that. I wish I was skinnier but  thats not the point lol... he said he wishes my ass was a little bigger. I don't know if I should be offended or what! What if I just out the cut said "I wish you dick was a little bigger" even if I was fine with his size I'm sure he'd get really offended... I didn't tell him I'm kinda upset about it. Should I? Or am I overthinking it?