3 month old nap times

My 3 month old usually takes a nap for a half hour every two hours. Yesterday and today he has been FIGHTING his naps SO BAD. He has currently been up now for 4 1/2 hours and is completely exhausted. I cannot get him to sleep. I have tried everything. I am so worn out because he’s completely cranky and I can’t put him down without him screaming. Any advice? I mean I don’t know what else to do.