Pre op diet and my body is in turmoil - tmi (monthly cycle)

I have noticed that my body is riding its roller coaster pre op with the diet.  I am hoping this is normal for some - or anyone.  My cycle has been off (well more like gone the last month) I actually kind of miss my monthly friend Flo. (Crazy I know!! )  I am trying to tell myself this roller coaster will continue to happen for a bit, just be patient but I admit I am going crazy