Question about which tools to use, bugs, the best way to implement a function, etc should go here. Don't forget to see if your question is answered in the wiki first! When in doubt post here.
Incidently, in case you're baffled by the meaing of the error: your code is attempting to reference two memory locations, that of a variable named "ah" and memory location 0. Since Intel architecture instructions only reference one memory location in a single instruction (there's no "mov address1, address2" instruction), you get the "too many memory references" error.