I had to drop my Adderall and Wellbutrin when I had crossed into a mixed episode. Those meds were making me far too anxious, 24/7.
I stick to my schedule, even though I am bored to death because I cannot sleep much at all. I still go to bed at the same time and allow myself to get up at the usual time, as well.
I agree that stress adds a lot to mixed episodes. I have been under a lot of stress now for a long time. In addition to dealing with MI and painful physical conditions, I also look after my elderly mother; she has had a few surgeries and has an ongoing serious infection caused by surgery.
H sometimes has to travel for work. His job is increasingly demanding every summer.
All too much to mention here.
I try to work on my stress level. So much stress gets the best of me via my own perception of stress/stressors. I have been trying to change my perspective so my "perceived stress" level are lower and lower, despite stressors remaining the same. (In other words, trying to minimize my reactions to stress.)
I hope you get a break soon.

WC