Drastic loss in cut

I started a cut 6 days ago didn’t feel like I changed much except stopped over eating and cut out all beverages except water and milk. Lost 2.5-3 lbs in weight from 182 and didn’t know how much muscle this cost me. I know I should shoot for .5-1 lb a week just curious if I need to start cramming food ASAP to minimize damage. I do feel like some was at least fat. Thanks