It looks great for a first render. Glad you still have your old files.
I still have a few saved up somewhere, but the really good ones were the ones that I have unfortunately lost, when a 2TB hard drive crashed two years ago.
And, I haven't modeled a guitar yet but I am about to do so for a character that I am going to sculpt in Blender.
RE: MY VERY FIRST 3D RENDER