Piece of skin on the nose could be left over from a shed, I personally wouldn't worry about it. A good digital thermometer is a good idea :jb:

If you're not using some form or thermostat or rheostat you should also consider getting one of those. It is much easier to manipulate the environment of your tank when you have a way to control heat output from your UTH; much safer for your snake as well.

Good Luck!