Neck shrinking

Patient: HI,There is something that’s been bothering me for a while, in the last 2 weeks my neck perimeter dropped 2 inches.I was tracking neck perimeter to know how much body fat I have while eating to gain muscule ( I’m eating whay more than I’m used to but still my neck droped this huge amount of size)Should I be worried??

Symptoms: NO symptoms, just a huge drop in neck size