I sprayed the windows with a glass frosting spray paint, inside the house. I did not wear a mask and now I am feeling shitty.
Will this get better on its own?
O man, do NOT do this......wear a mask, and mebbe open the doors before you spray.
Am I in trouble here or will this pass?
Two things you must do: First, get fresh air, and secondly, ventilate your home so that you do not have a potentially explosive condition (phone rings can ignite fumes, for example).
The only thing a mask would do would prevent you from inhaling the suspended paint. It would do nothing to protect you from inhaling the solvent fumes.
If all you have is a bit of a headache, fresh air will take care of it. If you have nausea and loss of coordination, you probably should seek emergency care. With one can and the use you described, you likely have not inhaled enough of a dose of the solvents and propellants to cause any permanent damage, though.
Once you have determined if you need more intervention than fresh air and have ventilated your home, take a shower and use lots of soap to remove any residue. Son't use any dishes that have been left out before washing them, either. And toss out anything that you intended to ingest that was out on the counter or table during your use.
That should cover it.