postpartum depression?

This will probably be long, I'm sorry. I'm a first time mom. I gave birth just a week ago yesterday, so I am 8 days postpartum.

I have an extensive history of severe mental illness and am actually disabled due to it. Because of this, my doctor was of course concerned of my risk of developing PPD. I took zoloft, a small dose, in the second half of my pregnancy and still am now.

I had a relatively easy labor and delivery. My physical recovery is going so well, which caught me by surprise. Minimal issues, the worst of my pain is awful back pain, and all over body muscle cramping/soreness.

The thing is, I am worried that I am already heading downhill as far as my mental health. I started out okay, I think. I didn't cry much in the hospital, my husband did more than I. I felt strange for sure. Maybe disconnected in a way. Things were stressful for sure. I haven't been getting any sleep at all. Maybe an hour or two every day at this point. We had to take our baby to the hospital over the weekend for phototherapy as his bilirubin levels were climbing dangerously high. The stress of that situation broke me a bit. We had only been home barely 2 days before that. It was agonizing watching him go through the 24 hours under the light. I didn't sleep at all.

We got home and followed up with his pediatrician and things seemed better with his jaundice. The next day though my husband already had to return to work as he only had 5 days of paid time off total. I dreaded it. Today is only his second day back at work and I'm surprisingly handling the days well enough. I feel decent, good even. More confident. Tired yes. But I'm noticing that as soon the sun sets, I'm a complete wreck. Talking severe depression, anxiety about my baby's health, extreme exhaustion and fear of the night ahead and overall just extreme sadness and crying, I want to sob and stop moving.

I have to get up and take care of my baby at night now as much as I can because my husband has to sleep for work, we need him to be able to work and function. The last couple nights my baby hasn't wanted to sleep much. Eating small amounts of formula every hour nearly it seems. Won't stay asleep, upset. Fussy. I can barely keep my eyes open trying to feed him or do anything at all. Last night as soon as we went to bed I cried. The next time he woke up and needed something I just couldn't move. I couldn't. I felt awful inside for it. I woke my husband up to take care of him and it was terrible. My husband doesn't handle it well. He was late to work this morning because of it. And I still didn't sleep more than an hour or two despite it. Right now we're waiting for our baby's pediatrician to call us back because I started worrying that he looks too yellow still and his eyes and all, I'm so anxious about his jaundice having somehow still not going away even though the doctor on Monday said he was good enough after the phototherapy he didn't need yet another bilirubin level test then. My anxiety is just getting worse.

I feel worse every day now. I'm scared honestly. I'm just so sad. I neglected to schedule with my psychiatrist all pregnancy because morning sickness in the first trimester had me in survival mode and I stopped doing much including bothering with returning phone calls. I am now scheduled to see my psychiatrist in early January, that's as soon as I could get in.

I just don't know how to deal with it all. The way I feel at night is so so awful and terrible and the worst my mental health problems have ever been because hormones and reality and how I have a baby now and he was born earlier than expected and it was so unexpected and I'm still processing it, I feel a weird sadness about not being pregnant with him anymore. It's just a mess.

I don't know. If it's getting worse every day is it heading into PPD territory and not baby blues?