If my 8 month old refuses to take a nap and I can tell he’s extremely tired, what should I do?

🐻bear

I’ve never had this problem before, normally he falls asleep within minutes but for the past few days he refuses to nap, he’ll rub his eyes till they’re red but when I set him in his crib he just throws his paci on the floor and stands up and looks out. I’m exhausted and want a break so bad but he just won’t sleep and I feel so bad ignoring him when he’s alone in the room. he’s never fallen asleep that way anyways when I leave him he just cries louder and louder. Any tips ?😕