My man gets emotional when *I'm* menstruating?!?!

We all know people say women act crazy when they're on their period, but my boyfriend is the one who acts like he's cramping and hormonal! He doesn't even realize it, but I've been observing it for months and without fail, when I start my period he starts acting crazy. And then I end up taking care of him because I'm just that stupid. I think it's unfair because my body is the one going through a lot. I don't understand what's the matter with him or how I can explain that it feels like there's a hot knife twisting inside my uterus while he's crying about having to go to the store. 😶 like seriously. Am I the asshole?