i have recently constantly been switching from nightshift to early morning shift. i work in private security. Right now i am leading security in a hospital and i don't know what to do, since i think i may actually collapse. I haven't had more than 5 hours of sleep a day/night for far to long and about 15 minutes ago when i went to do something my legs gave way under me and i banged against a wall. I am sitting down now, but i can't see the screen well and i am shaking. also i feel like i'm freezing to death. i could do some speed and get some energy back to make it through the rest of this 11 hour shift, but i am worried that i may actually get a heart attack because my heart is already beating extremely fast. my shift ends in about one hour and 23 minutes. i am seriously considering just chancing it and calling a cab home afterwards.