Q: Rear brake light, and some interior lights don't come on unless I'm braking

I have an irritating problem with my passenger side tail light. The stop light's socket that connects to the metal pin of the red lamp assembly does not always make contact. This means sometimes the red light doesn't come on unless I'm coming to a stop. I tried to tweak the socket to make contact with the metal part. It sort of worked, but the problem came back. Something new has started happening though: Now, the interior lights near the radio and the PRND12 bezel are off, and they only come on when I apply the brakes. Why do my dashboard lights only come on when I'm pressing the brake pedal? All the bulbs are new.