anxiety goes away when I have my period??

I suffer from chronic anxiety. but ive always been so scared to get on medication. its so bad that I'm constantly sweating, hard to go out in public or be around a lot of people. social media and school have been the worst as my anxiety progresses. BUT I've noticed that when I start my period each month my anxiety flips her switch and I'm able to have conversation, meet people and not panic 24/7. I feel like myself again one week out of the month. does anyone know why this is??? hormone balance maybe ?