Toto: Yes, kind of. Prepare yourself for epic amounts of waffle (it has a happy ending though I promise).
During a recovery 'period' (I'm making these periods permanent this time, just bytheby!) back when I was at an extremely low weight, I increased intake to 2000 calories AT LEAST daily, and for about 3 weeks I increased fairly rapidly to hit 96 lbs. However, after that time the weight gain literally stopped for another 2 weeks afterwards. My intake and activity levels were the same, and I was still badly underweight by most normal people's standards. I actually worried that I'd f'cked my innards up so much with my incessant starving that it was now refusing to digest properly.
Around this time my resolve to recover took a momentary blow and I started restricting very severely which caused my weight to plummet again. After rational thought kicked in, I decided that the reason for my relapse was due to such a dramatic increase in calories, and so reasoned that I would start slow with 1000 calories a day. And guess what? My weight not only sprung back up to 96lbs in the SAME bleedin period of time as it had when I was on 2000+, but it merrily carried on up to 100lbs! I went stir-crazy with anxiety let me tell you.
After doing some reading and research, I managed to convince myself that my body was just a bit overcome with joy at having food again and that it would stop as soon as all vital functions/repairs and so on had been attended to. I increased to 1300, 1500 then 1700 and my weight stabilised at what I would guess was about 7.5 stone (I had stopped weighing myself frequently by then, which was a massive help btw). As my intake gradually decreased back to about 1500, my weight started slowly dropping again, untill I got to the weight I'm at now (which is on the rise towards glorious health again woo!).
So to briefly conclude(!): During recovery your body WILL f*ck about. Unfortunately, the more desperate a state you're in the more it will mess about. But it does pass. You've just gotta grit your teeth sonny, and in the mean time remind yourself how epically ****e anorexia is.
I hope that helped some.
Also, HELLO to some new(?) anons and peeps peeping about. I may try and do some replies to you guys when my keyboard is not so tired. Though sometimes I don't know what to say to be honest.
Toodle pip for now though!