Should i tell him before i come over?

I’ve been talking to this guy for a lil over a month now. I just got my period and obviously we do hang out once or twice a week and we do have sex each time. But do u tell the guy before u come over like “hey just to let u know i won’t be able to do stuff this week” or do u just surprise him when u get there and when ur making out and it starts to happen just be like ope sorry i can’t. He’s a sweetheart and i know he’ll still want to hang out i’ve just never had this problem as usually i had boyfriends and were just a lil more comfortable talking about it.

So should i prepare him or nah? what do u do?