Know what I do when I smoke a bunch at a time and then can't sleep without it?
I sack up, and deal with it.
If that means 48 hours of no sleep before I can go back to sleeping without smoking weed, so be it.
So, in this case, thats what you should do, deal with it and try to get as much sleep as possible. If that only means 4 hours, its better than 0.
Also, a good reason not to regularly use pot. Although I've really got no right to talk. I smoke quite a bit.