That mainspring would have been on its way out, just adjusting the beat wont do that to a mainspring even if the strike side had locked up and in turn locked up the time side, if you were forcing the hands in this situation then the hands should have broken before the mainspring. As William suggested, check for damage, bent trundles in the lantern pinions and bent teeth will be the most common faults found after a broken spring.
Glad you still have all of your fingers and eyes, not a nice experience 
Paul.