I think your lines need a little more work, your strokes are kinda short and most of them dont connect properly leaving erm clumps of ink when they join. Perhaps you could go slower and join the lines up.Also the hair does have a fair amount of lines in it too, personally I find it a bit much. What I think might be good is if you gather them in lumps and draw flowing lines within to show movement and life in the hair.
Are you after a paticular style? most manga rarely have lots of lines in hair, but if you like it like that then i recommend looking up Wing Shing Ma and other Hong Kong artists
the way they draw and ink/paint hair is simply beautiful~ lots of lines lots of movement etc (lookup Storm Riders, Saint Legend, Weapon of the gods etc)
Only other thing is the hands and fingers, they are quite frail and bony lol I think you can skip drawing the lines in each fingers.
Yep Yep thats all~ :3 nice work on the colouring, it'll get better as you colour more and discover new techniques etc
(can't be arsed to check spellings)