Up and down consistently

I always feel so odd when this feeling of relief or happiness floods me... right now its because I feel useful and selfless... Helping someone out on a show practically for free feels good when they need my help.
But the past few weeks have been a roller-coaster: Up and down up and down, heights and depths and numbness in between... or distraction. I guess I always feel good when I'm crucial to a problem, when it's stress time and I'm the calm one handling things... It's so counterintuitive though, because when there's minimal stress and I'm second in command, I get bored wanting to make more creative decisions... But when the director falls apart, for instance, days before the show goes on, I'm on top of the world! Maybe because suddenly I have more decision making power?
When I'm the leader, the opposite occurs. Everything is fine and wonderful as I create and direct, until crunch time. Then I'm a mess and need lots of help... or else don't delegate at all.
A psychiatrist once suggested I may have mild bipolar II symptoms... Could this be a factor? I don't know because I do have anxiety about letting other people make decisions for me, so it feels good to be in control of my life. Maybe that's what it is: during my extreme downtime (I'm practically unemployed with a part time job that is very minimal) I feel bored and out of control, and thus depressed. But during my more busy times, like now, I feel elated, full of ideas, in control, and almost bursting with energy.
How strange that during both times, I have trouble sleeping... any thoughts?