I'm not saying you're manic, but i will say when we become manic the first thing to go out the window is insight so it's possible. How have you been sleeping? Eating? Any other of your typical warning signs popping up? I've done similar things and in retrospect I was manic (but I didn't know until retrospect).

Can you have a civil chat with your ex about how you feel? Maybe dig a little and try to see her side?