maybe you need more energy...try adding more protein to you diet(fish, nuts, chicken, beans). are you getting enough sleep? being in school you probably wake up earlier than you did during vacation. make sure you take an appropriate multivitamin. try not to work out too late at night......if you can get up early and workout before school that would energize you for the rest of the day. i think you have the will power...i just think you don't have the energy;those are two very different things. that's just my opinion. good luck with everything......don't over do it either.....you muscles need to recover.