Constantly internally screaming

I feel like I'm losing my mind. I'm 5 weeks postpartum, baby boy was a very sleepy newborn and willing to sleep in his own bassinet the first 3ish weeks. The last week though it's exclusive contact naps and he's now in the bed with me. When he cries it's 0-100 screaming and I sometimes just want to put him in a room and run away. We've also discovered that he has reflux, so any time he's laying flat it's instant fussing and grunting. I live in a country that will only prescribe medication if baby isn't growing well, that's not the case with him.

We also have a toddler who likes to climb in our bed at 4am, so my husband has started sleeping in her room because there really is not enough space in our bed for her and baby. The MOTN feeds and changes and baby's cries also wake her up early, which means we're all up early.

I miss my husband, I miss my toddler, she's been acting up so much lately. Especially the last week where baby has been with or on me 24/7. I'm so incredibly irritable and grieving what we had. Baby boy is very much wanted and I know this is just a phase but I feel like I'm drowning in sadness and anger. I resent the baby, I'm annoyed when my toddler is around because she's loud and asks so much attention of me that I can't give. I feel like I'm constantly internally screaming.

I keep see-sawing between rage and sadness. I'm counting down the days until baby boy grows out of being a newborn. With this being the second time around for us I can confirm I seriously dislike this phase.

I'm not asking for advice, just commiseration. I'm just so overwhelmed and need to vent.