This is my first time dolling and I was working on it for so long that I'm not really sure about if it looks good or not

Pleeeease lemme know if you have ANY suggestions (or even if you think it's good because that's helpful too).
Don't worry, it looks good! I really like the color palette and the shading you've done - it's evident that you're familiar with making artwork. :) However I suggest you should go over the ends of her hairstrands and the outlines a bit - she looks fine on the original size, but once zoomed in it's rather clear to see that the outlines are a bit too thick in places, which might make the artwork look sloppy. :) As I said it's fine on the original size, but if you wanted to improve it I'd suggest you shave off or recolor extra pixels at the tips of her hairstrands and the outline.