Why the hell didn't you call 911 in the first place? Suppose you couldn't feel her pulse, but it was there? And if you continued doing CPR? It would have messed her up for sure. Chances are, you missed the pulse and did very inadequate CPR- Trust me, ribs BREAK, or at least crack when you're doing CPR right, and if the heart stobs beating, it doesn't just 'start' on its own, let alone more than once.

Next time, CALL THE HOSPITAL.