Ok, what do you need to be sure to have in your bag for Hell Week?

Well I'm not sure if you are talking emotionally or literally but I'm gonna go the literal route.  You need to have everything for hell week that you'd need for the actual show.  I've stage managed lots of shows and here is a general list of things I ALWAYS have in my SM box:

Bandaids,
first aid cream,
q-tips
pencils,
post its
first aid tape for attaching mics
masking tape
gaffers tape
spike tape
sharpies in lots of colors
tampons and sanitary pads
flashlights
spares of any batteries used
tums
breath mints
individually wrapped hand cleaning wipes
Purell
bobby pins
safety pins
straight pins
needle and thread
extra buttons
self stick velcro
scissors
throat lozenges - I like Ricola
pocket knife
ball of string
ruler
tape measure
double sided foam tape
small packages of crackers
fruit or something for a diabetic
tylenol etc
allergy medicine like Claritin
hand lotion
Medical release forms for all cast and crew
ace bandages
emory board
nail clippers
cell phone
cotton balls
kleenex
zip lock baggies - lg and small
5 - 1 dollar bills

I'm probably missing something but that's all I can think of right now.  I use a tackle box.  I keep a list of supplies needed and check it after every weekend to see if it needs refilling.