Energy Levels!?

Hi everyone! I'm soooooo excited to have my surgery on Dec 17th! I am a full time college student finishing my degree interning as a student teacher. I graduate on Friday the 14th of December and I get sleeved the following Monday!! However I'm a little concerned about not having enough energy after Xmas break. I am taking over a teaching position right after Xmas break (January 6th) and I'm hoping that ill be recovered enough to handle being on my feet all day in a class FULL of students (we have almost 40 kids) these are 4 th graders and can suck the energy right out of you! When did all of you get your e egret boost I've been hearing so much about. Right now I'm 5'7" and 380 lbs. so it's hard to keep up with. I know it should be easer after I get some of this weight off