Electrical problem

So I recently moved up to washington and had to smog my stang here, during the process I think the cig lighter plug in they use mighta shorted something out or blown a fuse cause since then I've been having problems.

First after I left the smog place I noticed my speedo was now dead, then a day or two later my auto meter tach starts moving around on it's own while I'm holding a constant speed or idling. Then finally it was like there was just a massive draw on the electrical system cause the car died and was losing power very very fast, I couldnt even have my hazard lights on while waiting for the tow.

I just wanted to see if anyone here had any ideas before I start checking stuff out on it tomorrow morning.

Thats one of the problems, even with the car off it's like there is now a constant draw on the battery, it was down to 10v when I yanked it before heading inside, and it was only at 10-11v while the car was on.