My brake lights are stuck on. wtf!

[Isphius]

Ok i fixed the brake lights, but now i have a more serious problem. When I hit my brakes, My climate control panel flickers or goes out. And going down the highway, If i put the heat to off, It Makes the red batterty light go on, The brake light go on (dimly/flickering), And the voltage go up to almost 18 or less if i let off the gas. and when i switch it between high and off it causes the car to just die altogether for 3 or 4 minutes at a time. This is not good when your in 80 mph traffic and all your lights and motor die and your in the middle lane. To say the least, Im severly pissed at my car ATM, And i dont even feel like going out to look at it. It died at least 10 times on my way home. But when not on the highway, It seems fine. Except the CC buttons still flicker when i hit the brakes, But the car doesnt die. I seriously need some help with this, I dont know much about the supra wiring or what could even cause this. Its like the heater can just...disconnect the battery cable. BTW all fuses are intact, The cables are on tight, And the battery is a 2 month old 250$ gell battery. Any help appreciated