I am sorry you're so worried. First and foremost, as long as your dog is eating, drinking, playing and acting normally, he is not emergently ill. The white spot on the side of his nose could be anything from a pigment change (VERY common and normal) to a topical reaction to something he came into contact with while playing and exploring. Depending on if it is raised or tender, it could be a scab or a small growth (not necessarily anything cancerous). If the white spot is on his muzzle and is actually an area of hair loss, this could be due to anything from a puncture, abrasion, mange or ringworm. There are so many different things it could be, it's tough to speculate and I'm concerned that doing so will just make you more nervous.
The bump on his leg could also be many different things, ranging from a bug bite to a contusion sustained while playing. Since you are worried, have him seen by his vet when they open. Monitor his appetite and activity level. If anything changes, consider seeing an emergency vet. Otherwise, try not to worry and hug your handsome golden man :)
Good luck with your pup.......