Weight dropping

Hi mummies, I'm currently in my 2nd trimester 3 mths plus preggy. But my weight been dropping I do eat like 3 meals a day. The last weight I took on thursday is 57.2kg right now I took and I'm 55.9kg is it normal? At the first day when I know I'm pregnant I'm 58.2kg. I'm getting worry not sure why are my weight dropping. Any mummies could advise? Thank you! I'm first time mummy here