I thought this 6 week period of mania was unique, but in therapy I discovered that I've had many episodes in the past, I just didn't view them that way at the time. So...I relate. It's hard to recognize episodes until after your dx, and even then to figure out when they started or if it was just overnight. I've gone on spending sprees, been irritable or else elated, rapid speech, silly behavior, and didn't get it until recently that that was all part of the problem...the flip side to depression! So it goes. But you'll learn with time. I had to figure out the warning signs online too. Maybe print out a list of signs and every day go through them and see how many you have going on. If it's a lot, probably mania is coming or has come, if a few, it might be starting, etc.
Best of luck and