I took 2 zanaflex (tizanidine) last night i ran out of somas am i going to fail my urine test tomorrow?

No: Zanaflex (tizanidine) and Soma (carisoprodol) are muscle relaxants and not narcotics. If you urine test is to check for narcotics, tranquilizers, and other abused drugs it will be negative. These two muscle relaxants are not any of the drugs tested for in a screening urine drug test.

Depends on the test: Do they test for soma (carisoprodol) now ? that isn't in the standard panels but then, soma (carisoprodol) is only recently classed as a controlled substance. This sounds like you've been completely out of soma (carisoprodol) for 24 hrs or less. Varies with the individual but generally soma (carisoprodol) would still be in urine for at least 2 days. Don't overly flush the system with water/caffeine.