adding calories- when does the weight gain stop?

Hi,

I've been in starvation mode for a couple of months (eating about 1000 cal a day and excersising for about an hour), and I decided (after wonderful support from my boyfriend) to get healthy and up my caloric intake to 1700-2000 calories a day a 3 weeks ago. Since then, I've gained about 7 pounds.

My question is: when does it stop? There should be no reason for me to keep gaining at 1700-2000 calories, considering that I bike an hour to school every day and take long walks in the evening. I'm an 18 year old female, 5"3 and somewhere in the neighbourhood of 115-120 pounds (I'm not sure. Scales scare me so I usually avoid them).

I'd like to AT LEAST maintain this weight if not lose the few pounds to go back to my original weight. My jeans are pretty tight at this point, and I'd be lying if I said I was comfortable with it.

Can someone please answer?

Thanks ^_^