You poor soul. Insomnia is awful.
Don't overcaffeinate to compensate, or you will fuck up your sleep tonight as well. Drink plenty of water, eat well, and try to get out for some fresh air at lunch time.
Tonight, stay up for a reasonable amount of time (at least 9pm) before going to bed.
Are you on any medication for your anxiety? I had anxiety induced insomnia for a few months and was prescribed a low dose of amitryptiline. It did wonders for me.