1) If you are squatting in front of a mirror, try to focus on something reflected in the mirror instead of looking at the surface of the mirror. make sure it is high enough to be out of the line of sight of people walking (especially hot chicks!), because that can make the eye and head wander. I find it a lot easier to concentrate on my lift that way. If I can help it, I do not do any of my lifts in front of the mirror (squats I have to, 'cause that's where the cage is). People say they like to work in front of a mirror to check form, but unless you are a newb, you'll be able feel if you're not in form rather than having to see it.
2) Don't keep the bar too high. With practice, you'll be able to find the right spot for you. Try it with the bar and some 25's or 35's to see where it's the most comfortable.
3) Why no pads? 'Cause pads are for pussies.