Am I overreacting?

My LO is now 5 weeks about 4 days ago she started to be SO fussy.. she will not nap unless in the arms.. constantly fighting her sleep. I’m so stressed/overwhelmed, my partner has took paternity leave so he’s here for another month. The first 3 weeks he helped a lot. Once we hit 4 he got lazy doesn’t change her unless I ask, doesn’t burp her or get her unless I ask. Ever since she’s been fussy it’s even worse he takes naps every day, and when he comes out I’m still with her unless I ask him to grab her. I feel like I’m about to explode.. he goes to his moms house and I usually don’t mind until now.. he went yesterday from 12-3:30pm, came home got his beer and was in the kitchen watching videos on his phone, I’m with our LO 24/7.. I had to text him asking him to come get her, he did, (I usually sleep at 8pm) and then we switch. So that’s the only time he’s really “watching” her..

yesterday he gave her back to me because he had to use the restroom and of course he’s gone for 15 min I go ask him “what are you doing” he replied “ I’m brushing my teeth damn why you always gotta make it seem like I don’t help” I honestly didn’t even care to respond I just walked away, this led to him getting mad and not giving me a kiss goodnight. This morning I went to go get our LO her formula (I waited till he woke up from his nap) I left to get errands right when I come back he gets a beer from the fridge and runs to the room. I about had it, our LO is crying/ fussy on and off for 40min, not once did he come out and when he finally did, he left to his moms. We have another little one and I am holding it together so hard, I almost cried twice because I’m by myself our LO is so fussy and our other child is asking me to make her food.

I don’t even want to speak to him, I feel like I’m going to explode on him.

I don’t know if I’m just stressed? That’s why I’m asking if I’m overreacting

I can’t run away, I can’t up and leave our kids to go to moms house. If he needs a moment he can communicate that with me but he doesn’t.