1993 Olds Cutlass Ciera

[countrysis]

I changed the alternator for the third time in three years on my olds cutlass ciera. Now my horn doesn't work. I have looked through my chiltons and there is now troubleshooting. I wnt through the owners manual and saw where there is a fuse that might affect it, it was not blown, but I put a new one in anyway. Is there a wire that I could have possibly knocked loose? Where would I even begin to look.

Also, when my motor is running and I roll up the windows, it makes my engine slow very slightly, do I have some voltage issues or is that normal?