working with severe cramps?

hey ladies i need some advice.

so my cramps are absolutely horrible during my period and i skipped like four, so it seems like this time is really kicking my ass for that. i have an eight and a half hour shift today but my cramps are coming in so sporadically and no medication eases them. on top of that, i’m super nauseous, have a headache, and getting hot flashes. how do i call into work without seeming silly? i called in a couple weeks ago with severe nausea so i don’t wanna seem like i’m trying to get out of work but i can barely even function at home.