Sounds like you're still at work...
try...going to make a hot cup of herbal tea, I dont know what plan you are following, but did you bring any snacks? If you did, just place a piece of it on your tongue and savour it. Relax, enjoy your tea. Then if you can, try to get a little walk in...just enough to clear your head a bit, breath deep and relax.
Then when you get home, deal with what you have to, and as soon as you can, hop into a hot bubble bath or curl up into bed with a good book!
Hope this helps a bit