I had too much caffeine this afternoon and now I can't fall asleep. What to do?

Yesterday I had to be at work early in the morning for a double shift after having worked until late the previous night. I never drink coffee or anything else that has caffeine, but I was in dire need of a boost midway through my day so I drank a huge cup of freshly brewed coffee. I have another double shift this morning (I have to be up in just about 4 more hours) and I’ve been lying in bed, willing myself to sleep, for the past 3 hours or so to no avail. I’m so exhausted and yet can’t fall asleep because of that darned cup of coffee many hours ago!!! I’ve tried counting sheep, hugging my pillows, “yelling” at myself internally to fall asleep, etc, etc, but nothing seems to be working. I’m at my wit’s end and don’t know what else to do. Any suggestions (besides “never drink coffee again”) to at least help me make use of the few hours I have left before my alarm goes off??

Thank you!

And I swear to never, ever drink coffee ever again!!