When you rub you hands what changes? I did it for the first time today and it felt like the colors went a bit stronger.
After i rubbed my hands behind me i saw a paper, i held the paper and i was kindof more lucid/vivid. Could it be the rubbing or that i just felt things in the dream?
Rubbing your hands stimulates your touch sensory, which in turn immerses you more into the dream state, you get literally more “in touch” with your dream body, and and such with this the dream is reinforced. It is one of the many practices to get dreams more stable and vivid, so no wonder 
Gratz for the LD by the way 
Cool 
Btw its not my first time to LD 
But to rubb hands yea
I always rub my hands when I get lucid, simply because everyone says to. I always think “meh, this isn’t going to work,” but then when I do everything sharpens up very quickly. Its like putting your glasses on in the morning. Although rubbing my hands usually works, just looking at my hands works even better. Its the first thing I do when I feel my Dream/lucidity fading.
lol i love a good pun!
i haven’t tried this technique yet, but it sounds like it works well so as of now i plan on trying this in my next ld! 
A few guides on this, also grabing something and pulling yourself twards it has the same effect, so pretty much anything that reassures your SC that your dream is real.