please help :'( new here, need explaination

sel_ana

I had lost 20 kgs in last year but I was unhappy cause I had become weak and extremely thin in some parts like around neck.ALso my skin had become lose. So I hired a personal trainer as my weight dropped to 47 from 50 kgs which was really unhealthy.She told me to get to atleast 55kgs. I have been doing strength training from last 1 month with balanced healthy diet and I was very happy as I had started noticing that my muscles were getting tighter and the lose part around thighs and hand improving.ALso my stomach had gone pretty much inside but yesterday when I tried my jeans, I cudnt fit into it properly. it has become tighter, also my upper body. I. cent % sure I haven't increased in size as I can see that I have improved a lot and I look much better now. but whats the reason of my clothes getting tighter? I really explanation for it. my inches has nt increase, infact m getting toned. pls help, my weight is 52 now and I thought thats because m gaining muscle

Squamation

You're getting bigger.

You may not be gaining fat, but muscle takes up room too. Have someone else tape you (as it's very difficult to tape yourself accurately) and keep track of your measurements.