help? (zaleplon) and adverse stimulae peak

Greetings,
I've Meniere's Syndrome in both ears with loud tinnitus, chronic tendonitis in one wrist in periodic +8 pain, and now, since late May, I've not slept from pain resulting from herniated disc at L5-S1, which hurts +10 like a toothache all the time, all the way down one leg. Dr. gave me zaleplon for sleep. In desperation, I tried 90mg. over 20 hours, with no result. Anyone know about this med and possible consequences of excessive doses? It was NOT an intentional o/d. I do not want to o/d or pass on. But, with all these adverse stimulae, its just a bit much.... I cannot continue without sleep, as is true for anyone, I'd imagine. Any counsel anyone can offer will be valued highly. I welcome 'e' mail: Ryokan@webtv.net.

Thank you very much....
Lee