You have described feelings and experiences that are apart from your normal self. It sounds like you are having some anxiety mixed with depression (and some euphoria maybe). I’m not sure if that would qualify as a mixed episode unless you are having more manic symptoms, and I realize everyone experiences their own set of manic symptoms.
I too have a hard time distinguishing if whether or not I am in the midst of a mixed episode. My pdoc did say when I alternate between crying (doubtful) and excessive laughing (feeling elevated but not happy), am tightly wound up like a rubber band inside and talking to myself incessantly, and that lasts for a week or longer, then it is probably (not certain) a mixed episode. When I start to exhibit bizarre behavior when alone that cautions me to be self-conscience enough to try to avoid embarrassment in public. I am fortunate that I have my own office at work so it is easier for me to hide any bizarre behaviors.
I am possibly entering a mixed episode now based on how I have felt the last few days and my mood chart here indicates that as well. I will try not to dwell on it to avoid that panicky feeling. Hope you feel better soon.