checked dash lights because some were out, but none were burnt out, and now, none of the bulbs will light up.

 

Not sure what type vehicle you have, but may be fuse, or headlight switch, just a couple things to check out.

 

Most of the trucks have a circuit board where the bulbs lock in place. Take a pencil eraser and clean all the copper traces, and all the bulbs should burn. If you took the dash apart with the battery connected, you might have shorted something out accidently and took out one of the fuses.