First, congrats on making a big step towards getting healthier. I know it's not an easy one.

You probably won't like the advice I'm going to give, but that won't stop me. Here are my creds: I've been living with ED for 34 yrs (bulimia for the past 25). Sometimes I kick his butt; sometimes he kicks mine. Right now, I do most of the kicking

While you are in a safe place, DO NOTHING. Do no exercises until/unless you are allowed. Yes, you will feel anxious and worried. You're expected to feel that way. That's one of the disordered thinking parts of ED. It is also a part that, with competent help, you can learn to overcome.

I hear u - exercise is a stress reliever. But If purging is removed as a coping skill, it is more likely that one would compensate by over-exercising. At least, that's what I did. So while you can, take all the help you can get, drop the negative coping skills that lead you inpatient to begin with, and start to climb your way out of this hell hole.