your mouse pad? mouse pad is just the surface you put it on.
since you spoke of your laptop I assume you mean your track pad? You touch it with your finger and move the cursor?
Trackpads like a small contact area, meaning like make your point of contact as small as you can. Don't lay your whole finger on it or it wil confuse the signal. Long fingernails can be a problem as well. If thats not the problem and the pad is really reversing direction, is there some sort of potential option to invert the movement?
what model laptop do you have?