1994 Mustang power windows

The power windows are driving me bonkers. The right one stopped working.
Checked all the switches and fuses and connections and it's all fine. When I
try the right window it does absolutely nothing. The drivers side was fine
until today when it wouldn't lower. I hit the glass lightly and suddenly it
started to work again. It happened a few times again today. Then as I'm
driving with the window all the way up I could hear a faint creaking noise
from the drivers window as if it wasn't up all the way. Is there some kind
of stop that tells the window when to stop moving and maybe it's getting out
of adjustment? Or is it possible the parts that move the windows are getting
stuck or jammed? Any ideas or suggestions would be great.

Thanks!