So Many Complications

This is my first time installing a car stereo and needless to say, I'm having trouble. Where do I even start with this?1. First, I disconnected the battery. After installing the head unit, I decided to check to see if it would work before I put the dash panels back on. So I reconnected the battery. Well, my truck has one of those switches so that I can turn off the passenger air-bag. I had to disconnect the wires to the switch to get the panel off. When I checked the CD player, the truck seems to have gotten the idea that my airbag was deployed. Now I've got a blinking red light on my dash. I think I can get it fixed at the dealer when I get the oil changed (got a coupon).2. My CD player's got these knobs on both sides. It's a Sony CDX-MP70 . One for volume and one for skipping tracks (instead of buttons). They don't work. Well, they work when you mash them like buttons. But they don't work when you turn them. The instructions said that I have to hit the reset button behind the face plate, I did that 3 times. It clears the mem but it doesn't fix the knobs. That's also what it said to do in the troubleshooting section. I'll call tech support sometime during the day and see if there's something that I can do about that.3. The sub I have is only temporary. I swiped it out of my old car. My sub box slid over and I pushed it back. When I did, one of the wires came loose and shorted. It blew a fuse in the amp. I replaced the fuse but it still doesn't work. The red LEDs on the amp still light up and that's about it. I took the cover of the amp off and nothing looked or smelled burnt. I have no idea what to do about that.Well, what do ya think? Am I hopeless or what? --Jason