the 4 month sleep regression is REAL

Alright mamas, give me your best advice! Please, before I fall asleep sitting up 😂 little dude is either going through a growth spurt, teething, hitting a sleep regression, or a combination of all 3! 
He's crankier than ever. Putting his whole fist in his mouth. Slobbering like crazy. Wanting to eat more frequently. And such a hard time sleeping. Not napping quite as well unless you are holding him. And while he used to sleep 9-5, he now wakes up multiple times just crying. I've been feeding him 1 time in the middle of the night and he seems like he really needs it. He chomps at the boob like he's never eaten before. 
Any thoughts? Combination of all 3? We are on day 3 of this. Please send help and coffee 🤣🤣🤣