First of all, well done on starting to eat more. Thats a really big thing for some people and you've done well to stick with it for 3 weeks, even when you've seen a gain. I think its normal for you to gain some weight back after being so restrictive for a while. How many calories are you eating now? And how have you bumped it up? If you have added more fruit, veg, whole grains etc and arent just munching down on mars bars now you should be doing fine