lost iTunes music

I've recently had a new phone, so I went to put music onto it using my Windows laptop with iTunes. Before I added music to my iPhone, iTunes requested that I updated it before adding music, so thinking it would be beneficial, I went forward with the update. Since the update, I've not been able to locate any of my music apart from my purchased music.

So just to clarify, all of my purchased music is here, but none of the music I've personally added is here e.g. CDs and music from my laptop, like it used to be.