How To Treat Body Pain And Fatigue Caused Due To Stress?

hi, i just got a job and ive been working about 40 hrs a week. Today i have a 12 hr shift at 4p. I wasnt home from work this morning til 5:30 am and i dont get off til 4 am tomorrow .. My body aches. im exhausted and my mood i just starting to decrease. I am irritible and dont want to talk to anyone, although i am a waitress and that is a huge part of my job. i need the money so badly, but i cant handle the soreness and exhaustion that comes along with it.