No I'm not craz.... well ok yeah I'm crazy, but not because I named this piece "Angry Squirrel".
When I started this sketch, my best friend thought I was drawing a squirrel and he just thought I made him angry looking. And also if you glance at it out of the corner of your eye, it kinda does look like an angry squirrel. lol

Thanks to Robbo for the reference picture.

Done completely with:
0.3mm mechanical pencil
0.2mm mechanical pencil
smudge tool
gummy eraser
12+ hours to complete