1993 Pontiac front brakes

I have a 1993 Pontiac Bonneville, 4 door, with a 3800 engine V6, and the milage is 103,000 miles.
I changed my front brakes but the bell still dings as soon as I hit the pedal and the brake light comes on. I know I did everything right. I work on cars as a hobby. Do I need to reset the code or can I just unhook the battery cable? I bought the car off a guy that really abused this car and let the brakes go down to the calipers. The rotors were really bad. The brakes work fine after I changed the rotors and pads. But wont stop dinging and the brake light wont go out.

Thank-you for the info, the model makes a big difference to check on info.

There are 2 main reasons for the light to come on:
PArking brake pedal partially engaged, or low brake fluid in the M/C. IT may be affected if there is a problem with the ABS.....if it has it.