"I'm trying to just close my eyes, relax, and breathe. The only problem is, after a second I forget that I'm trying to calm down and let all the panicky thoughts back into my brain..."

This drives me crazy. Crazier than when I start. I grind my teeth and I try to put my finger in my mouth (when I'm alone at the computer so people don't think I'm hannibal-lecter). Then if I don't start biting my nails, I stop grinding my teeth for a minute, remove my finger and start grinding again. Closing my eyes and breathing is like mission impossible.

"I'm trying to keep from scratching like I tend to do when I'm freaking out a lot..."

Sorry to t/j but is this anxiety related? I've had ridiculously itchy legs since I can remember. I've always layered on the moisturizer but it never really helps, my skin isn't all that dry, but that's all I/senseless-doctor can come up with. Now that I'm older and more conscious of it, I notice I do it when I'm panicking. You may have just solved the greatest medical mystery of my life!!

I hope you feel better, it's always hard to get back to normal life after being in a peaceful place. Especially with a new job (I just started one). I'm guessing you like music if you are willing to teach it, I don't know who you are teaching, but try to show them what you find enjoyable about it. If the warm ups are hard at first, see if it's a level that they can get to, if you don't think it's realistic, revise them. That's the lovely thing about teaching, YOU are in control. Do you have a calendar or phone you can put a reminder on for the background check? Can you do it right away so you don't have to worry about it? Changing lanes makes me nervous when I'm driving, try to stick with the parts that you are more comfortable with. I think anyone would be awkward at first, whoever you are teaching will probably be nervous too, so try to find a happy medium dual awkwardness. (yeah, I know that totally doesn't help but I'm a "fixer" so I need to feel like I have an answer)

There's a difference in location/instrument/I don't know what level you play and what your teaching/every other factor imaginable. BUT, here is what my piano teaching friend said,
$10-$20 per half hour depending on your qualifications.
I'm not sure if it would change at all but here our minimum wage is $10.25/hr so.....ya.
Also we have a "Royal Conservatory" (http://www.rcmexaminations.org/index.html) and my musically knowledgeable friend suggested that if you contacted them, they could give you guidelines. It seems Canadian but it says it's available across North America, so maybe it's worth a shot?

I'm putting an end to my rambles now, hope you feel better