A tip to relax your jaw (for those who have this problem) is to put your tongue on the top of your mouth behind your top teeth - then you can't clench your jaw...
I tend to get racing thoughts when ever my mood goes a even just a little bit up or down. Just they get nasty when it goes down. a couple of tricks I use are writing in a notebook to get the things off my mind until the morning, reading until I'm really tired, seroquel tablets, and mini meditations - just think about one verse or passage for 5 minutes and don't let your mind go off topic...