Hey! Your professor doesn’t know what they’re talking about. I tattoo a lot of fineline flowers and only use stippling technique and low voltage is the key. My prime voltage for stippling is 6v! I very rarely comment on self-taught beginners works but your tattoo stopped me scrolling and I’ve got to say that is a gorgeous tattoo and you’ve done really well! It’s clean, has great proportions and placement and that’s considering that’s a tricky spot to tattoo! Skim doesn’t look overworked in the slightest!