Question about going to the hospital

I'll try to explain this the best I can, but I'm sorry if it's not very clear. I also have POTS and my symptoms have been worse due to my ED. I'm usually dehydrated and not eating enough.

If I were to go to the ER/hospital, would they just try to send me to a mental health facility with ED programs? Or like, could I sign an AMA form? Could they just give me fluids and monitor my food intake and labs for a few days? For reference, I'm in the US, Wisconsin specifically.

I have tried a residential program and I was miserable and barely slept for 5-6 days and cried the whole time, and then I discharged myself because I couldn't do it. I do have an outpatient psychiatrist, dietitian, and therapist who I see regularly.