Anorexia Recovery & Treatment

I just started a partial hospitalization program to recover from anorexia and i really need to gain some weight. (I am 17, 5′4 and 80lbs, but i have never weighed past 87lbs in my life- i guess i just grew and never gained weight). Anyways, i’m not sure how much weight i will have to gain before i get out of this program and can go back to school, but im thinking maybe like 15-20. My fears are, the other girls who are further along in the program have to eat soooo much food. The dietician said it’s because that once your metabolism gets going again, it goes into overdrive. So im concerned about having to eat that much just because i dont think my stomach can handle it. I am on a lower calorie plan to start, but even now, my stomach hurts and i get really bad gas after i eat my meals there. Will this improve? Also, if i gained the weight, will it be evenly distributed? Will my breasts still grow? I also hope to do a little strength training once i get out of the program, but for now im not supposed to be exercising. Is this ok too?
Sorry for all the quesitons. Thanks for your time

When i entered recovery for anorexia 4 weeks ago i was 5′8 118 pounds and they put me on meal plan c (2000 calories) because i needed to gain weight and because i was exercising alot. A day after being told i needed to follow that meal plan, i was told by my doctor that i could only go for walks because my heart rate was 41. now, 4 weeks later, i am at 122 lbs and they just changed my meal plan to meal plan b (maintain weight) because i still cannot exercise; not because of my heart, but because i was over exercising last week when i was told by my doctor it was not safe to exercise. My question is, now that i am on meal plan b (1800 calories) and not exercising wont i gain weight? why would they put me on a meal plan to maintain weight if i am going to gain weight from it?

i was diagnosed with anorexia a few weeks ago, with a BMI of 14.5 i was told i would be hospitalised if i didn’t start gaining weight. i was given a meal plan by my psychologist, which probably totaled around 1800 to 2000 calories a day (i had perviously been eating around 500 a day, at my worst point around 200).
for the first week i stuck to the plan completely (basically had to force all the food down my throat but i won’t go into how hard it was). i’m weighed by my psychologist once a week and i found it really hard to see the weight increase. so for the past two weeks i’ve not been completely sticking to my meal plan. i’m definitely eating way more than before – probably an average of 1300 – 1400 calories a day. despite this, i’ve gained 2 kg in 3 weeks. i know i should be happy i’m getting healthier and stuff, but i’m finding it VERY hard to deal with, especially because i didn’t think it would be possible to gain so much weight on the amount i’ve been eating. surely 1400 calories a day isn’t enough to be gaining so fast? obviously it is, but i’m so confused. is this normal? will i continue to gain weight this fast? any advice or experience on this would be very much appreciated…

My bmi is 14.8, I’m 16, and 5″3.5
i’d like it to include liquids… i can blend up complan or milkshake/smoothie/nestle build up supplements.
recommendations please.