Am I wrong to feel like he's an ass

Okay so my fiancé has dental issues like really bad Saturday morning he wakes me out of a dead sleep screaming and crying in such agony I thought he was dying, anyways he's complaining that his teeth hurt so bad he doesn't know what to do after arguing with me for almost 45 minutes he finally decides to let me take him to the ER granted we've been before for the same issues and all they did was give him a muscle relaxer anyways same thing happened this time, and so I find an Er dentist that can see him first thing that morning. She tells us he needs an extraction, a root canal and filings and crowns. Basically his teeth are fucked, so she sends him home with pain medicine and it's still not strong enough to get rid of the pain here's my issue I'm bending over backwards to make sure he's comfortable and that he doesn't have to do anything I'm catering to him hand and foot and yet he speaks to me like I'm a dog snapping at me making extremely rude belittling comments the list goes on, so I try telling him to please not speak to me that way it's hurtful and his response you don't understand  in pain it ****ing hurts so yeah this is how I'm probably gonna speak to you until it's fixed. Well he has an appointment in the morning and I've been trying to explain that since we don't have the money right now we could set up a payment plan with them, he says I think I've been to the dentist enough that without insurance you can't do that, (with rage and sarcam) so I say calmly and quietly well let's just be optimistic about the situation. No any positivity I'm trying to bring he's not having it. I feel so broken right now I can't call my mom and tell her about it cause she already wants me to leave him ( they just don't get along he really is an amazing guy treat me right and everything except for the past week or two) ugh I just need reassurance that I'm not wrong in thinking he's being a complete asshole to me for just trying to help.