Any advice for managing anxiety?

I realized at about 10pm that I may have missed work this afternoon due to unclear schedules (there are two or three, and they don’t always show the same information). My employer employs a no call/no show policy, so there’s a chance that I’ll get to work tomorrow and find myself without a job.
I’m reasonably confident in my ability to talk my way out of the fire, but there’s no guarantee.

And so, I’m a tad bit anxious, and so I feel like I ODd on chocolate, which is uncomfortable. Any suggestions?