Is my Stereo messing up my electrical?

[Salvydoor]

I have a 2008 Altima 3.5
So about a month and a half ago while driving both the battery and brake light came on simultaneously (which I found meant an alternator issue) but they would only stay on for a few seconds and then disappear. It would happen randomly while driving. I drove it like this for about a month figuring it was a bad sensor but after that first month the car would pop the lights up, and sometimes it would go into limp mode. That's when I decided I needed to bring it in.

After giving a quick look I found my negative battery terminal to be pretty corroded and figured that was the issue. So I took it to my local Nissan Dealership (my normal mechanic was busy) and told them to check it out. After they checked it they told me my Alternator was bad and my positive wire needed to be replaced. Total price was going to be around $950 with $700 of that for the alternator. I knew my regular mechanic could put in a new alternator much cheaper so I told them just to replace the wire terminal so they did. When I got the car back I took it to my mechanic and he replaced the alternator.

I've had the car back for 2 days now and when I drive it, whether on the street or freeway, all the lights on my dash turn on and the odometer drops to 0 even while it's moving. I have a video but I don't know how to post it. So I don't know what else could be the reason behind it. Also worth noting but I have a stereo system with 2 12" subwoofer with a 1100 watt amp. Could my stereo be affecting this or what do you guys think?

[Salvydoor]

[youtube]https://youtu.be/FLLOcHjRnnY [/youtube] this is what's going on. Also noting that I had the stereo professionally installed in a shop, I didn't do it myself.