My 2001 Lincol LS seems to be having some issues.

My 2001 Lincol LS seems to be having some issues. First the horn was acting funny by only working occassionally as well as the steering wheel radio and cruise control buttons. Now none of them work. At one point, volume control would change the radio station. Now it seems as though my rear brake light goes in and out triggering my dash light to also go on and off, only when the brake is applied. There are times where when I brake, both tail lights brighten and other times where only the right tail light brightens. I believe that the same bulb is used for the brakes and illumination. Any one have any ideas, I'm afraid that I might have a real electrical problem on my hands.