frame of mind
A person's outlook, mood, or attitude. I'm always in a much better frame of mind if I have a chance to unwind after work. You've got to improve your frame of mind if you want to get that job. No one's going to hire someone who isn't confident in their own abilities!
one's frame of mind
Fig. one's mood or mental state. My frame of mind is sort of low at the moment. I've had a very bad day.