the Mean Lady

My kitchen faucet (a Kohler Forte) was leaking only when the water was running and only when the faucet is turned to a specific location. The leak was coming from underneath the handle. I'm no plumber, but after hours of online research and what wimpy tools I had, I was able to take the thing apart and fix the leak. The leak stopped. Yay!! But now there's a new problem... When I go to turn on the faucet, the handle is very tight and takes much effort to pull up/down (on/off) and left/right (hot/cold). Boo!! The handle wasn't this tight before and this doesn't bother me so much, but I'm thinking that this can't be good for the faucet since it feels like the action of turning on the faucet is going against its will.

Anyone have a clue what I did wrong? I did turn the mounting nut as tight as I could, thinking that this was causing the leak. Is it possible that I turned it too tight?

Any suggestions, thoughts or ideas would be greatly appreciated. Thanks in advance!

I have the Certificate of Title which is already signed off by the lienholder releasing interest because I paid off the car loan but I am not sure what part(s) of the form I need to fill out and where to sign before sending to the DMV. This is for the state of California. Thanks!