I would see your GP because it is important that you get some sleep. I suffer from the same problem and actually take tablets long term from anxiety. Sleeping tablets can make you feel awful the next day and that will affect your work. I couldn't cope with Nytol at all and the herbal variety did nothing.
Your doctor may well prescribe a short course of sleeping tablets to get you back into a pattern of sleeping, but you need to address the anxiety problem before you can really benefit.
One thing I have learned is that if I can't sleep it is best to get up, get out of the bedroom make a cuppa and perhaps read for an hour. I often can then go back to bed and fall asleep. Laying in bed getting more and more awake makes it so more worse and problems get exaggerated out of all proportion.