brake lights stuck on

I have a 90 k2500. My brake lights are stuck on. I pulled the B/Lt switch to test and they stayed on?!?. Ck'd fuses....all ok. when I reinstall B/L fuse they go out for about 1 minute {if they go out at all} and come back on. When this happens my Parking brake dash light comes on too, When I tried my hazards, they light up but stay lit and dont flash. All turns seem ok and park lts seem ok. Would a bulb going bad cause all this? They all seem to work properly. Or is it more likely a ground issue?Any help would be appreciated. I HATE ELECTRICALS

All fixed. Found that another switch mounted right behind the pedal and under the brake light switch had hit the brake light switch adjusting lever. I dont know what this other switch does. It's a square black plunger and the wires go to the brake light switch mounted on the pedal arm. It's unplugged now and everything seems to work good. Anybody know what this switch is for. Gonna call GM and ask them if no one knows.......Thanx