Ladies please I need some advice!

So my son who’s two months old hasn’t slept all day today since 11:30 am this morning. The whole day he’s been fussy. He would fall asleep for literally 5 minutes that’s all. And he’s been crying so much I don’t know what to do. He calms down but then starts crying again. I checked his fever and he’s fine I just don’t know why his being so fussy. Right now as I’m writing this I’m breastfeeding in bed and he’s falling asleep. I know he’s sleepy but he just won’t sleep. Yesterday he was fine it’s just today he’s like this. Please advice me