Zak, sometimes crying is the best option for situations like this. Called manly tears.
Yes, he will be missed, but death is a part of life. You are going to have to experience facing other people's and your own death in your life. I think it is best to think that he's on a trip instead of what you are doing right now. I'm pretty sure your Uncle wouldn't want you to rot yourself for days, maybe weeks, maybe months.
I think it's best to cry all your tears out for now.
I recommend you listen to some songs composed by
Joe Hisaishi.
Listen to these music
in the order I posted
The Rain - Joe Hisaishi
Inochi No Namae - Joe Hisaishi
Merry Christmas - Ryuichi Sakamoto
Itsumo Nando - From the movie, Spirited Away
I will post more good music.
Also, Rest In Peace Zak's Uncle.