I left my stupid lights on by accident and the battery died, so I had to jumpstart it with my dad's car. Now the radio, aux, and all the others are gone. There's no light or anything, it isn't asking for the code as well.

How do I fix this? I just got the car a month ago, I don't even know the serial for the radio unit so I can't get the code (if that was to solve it). Do I have to press something to bring up the code command?

All help is welcome, thanks