Do you have a car? If so, sleep in your car in the work parking lot. Ideally when the manager isn't expected.

I suggest you take caffeine pills--no more than the box tells you!

Are you in a rural area? Making friends as an introvert is, well, I have been there. See if you can find a Methodist or Presbyterian church or something low-key. Maybe a synagogue if you are near one. Maybe there's even an unlocked church you can pray in and doze off in when you aren't working. Or a library. Libraries can be okayish to kill time at, maybe nap in a chair.

Churches/synagogues are ok for making surface-level friends. You can also probably wander on any community college areas without much suspicion, though if you drive to one, you might get a parking ticket.

Lights. People. You need these things. If all else fails, go to Dollar General and get a big thing of salt. Put a circle around your bed, then get in it. And stay under the covers until daylight.