All of the new changes that come with adolescence contributed to it. I clearly remember that I felt manic right before I was going to go on a trip with my family to England when I was fifteen. I experienced mania and high anxiety right before going on the trip, and I went into a mixed manic episode during the trip with psychosis. It was hell. I only remember bits and pieces of the trip. I think the stress and anticipation triggered the episode, but apparently, I continue to have recurring episodes. So that experience just happened to "kick off" what was yet to come down the road regardless, if that makes sense.