I don't have a solution to the problem you're having with your schematic, but I am working on the same thing as you are (amplifying the sound of a small mic) and here's what I've got so far.
Whatever you do, don't use this
scheme as it simply doesn't work. It is well explained though, so you might be able to use it as reference.
Instead have a look at this
thread. The scheme this guy uses looks very promising and I'm actually gonna try a variation
on it myself this monday. Now it may not be the simplest scheme out there, but I think it might just be the simplest scheme that will actually work
whatever you do, please let me know if you get it working!