the mouse was bouncing all over the screen! it was clicking and highlighting stuff - it had a mind of its own! I thought that the NSA had hacked my computer!!!
So well; I had gotten confidence opening the machine from when I replaced the battery using the advice and materials I got from the ifixit; so I said that I'd do myself again!
This is the best website! I love it! Just do what they tell you; follow the instructions and all shall be well :)