welcome to the world of training!

best way to toughen up those knuckles is hitting the bags. get your coach to show you the technique and hit that heavy nag. dont go crazy on it, use proper combinations, with power, but dont go over the top. your guard should be up all the time when your throwing punches.

pressups etc will increase not only your conditioning, but your power aswell, so drop down and give me 20 maggot!

as for speed, im not too sure myself. i use a speedball (although they are weird) and shadow boxing, the mother of all excersizes. get infront of the mirror and throw controlled but fast punches.
thro real combos and keep that guard up. move around as you throw, duck, parry and punch for timed rounds. look in the mirror to see if your telegraphing your munches, and make sure your guard is up.

good luck

alex