I don't know how I did this but it was a complete brain fart. I'm working on my stair risers and end caps and I primed with oil based Kilz but forgot to get oil based paint and painted the first coat of paint with latex. Am I screwed? I even mixed oil based Penetrol in with it haha. I feel like such an idiot. What should I do?

You can use latex paint over oil based primer. You are fine.

What did you add Penetrol to?

Edit to add: People use oil or shellac based primer all the time with latex paint. The primers are designed where you can use any paint over them.

Added penetrol to the water based paint.

This was the way my dad used to paint things.

The old wooden garage door was 2 layers of oil based paint (before assembly) and then 2 latex layers. Doors still look good after 30 years (last I looked).

~egon