on touchups I might do $30-$60 range, depends on how much they end up doing,
gloves, needles, ink, ink pots, saran,paper towels, etc etc , if you think about it they are using a lot of supplies.
plus their time.
call and make an appointment to go see the artist that did it and let that person know your thoughts.
most good artists that I know will happily do a touch-up, for free,
if they do,be sure and tip them.(for cost of supplies)
Feet are different healing because generally there is reduced bloodflow that far from your heart.
IMHO you're going to have to give it another 2-4 weeks
Try walking on your feet, not the tattoo!
Seriously though, that's very common for lower leg tattoos, give it a week. Then give it 4-8 weeks to heal completely.