It's actually on my cousin he couldn't sit anymore than the 3 hours so its going to have a 2nd session on it. I agree it could have been done better my mentor actually said the same things you did.. he wanted a "dark and sinister" tattoo so thats I aimed forThat's a huge piece on a very prominent area for your first tattoo. I think it may have been a bit over your skill level. Here are a few of my thoughts:
1. I love the drawing.
2. the lining, in general, is pretty clean but there are some lines I can see right away that will probably fade/disappear through the healing process. There are also lines that don't meet, and even forgotten lines you didn't put in that I think messes with the overall piece.
3. The shading is pretty smooth but I think you could've played with the values more to have more contrast and depth. Everything kinda blends together.
It's ok to do smalled pieces as a beginner.
overall I think its a cool tattoo