I am diagnosed with bipolar, borderline personality disorder, and generalized anxiety disorder.

Sometimes it is difficult to know the difference between normal, or symptom of disorder for me.

I have this thing you described. What is normal, and why do my emotions feel like they are just floating from one area to another randomly and without triggers.

I don't know why, but I have that too. Good luck to you, discovering what entertains you, and invigorates your mind will lead you to have less of that.

A sense of purpose takes it away. Having too much mental free time for me isn't always a good thing. Sometimes it is, because it calms me down, but other times it is just fodder for random sad thoughts to take hold.