Your stack pops because you're calling changeState from within changeState.
The proper way to go back to the previous state is to do (= state X) (= cycles Y) where X is the target state - 1, and Y is something nice and small but not zero. A single cycle will do for a near instant kick back to that earlier state.
Oh, and self cue: is Bad Form for the same reason, that just indirectly calls changeState from within changeState.
Also, your parenthesis seem to be broken.
(1
....
)
(2
....
)