less colors can look better. also makes animation and editing easier. but if it looks better with more colors keep it as it is. just because it is common for pixel art doesn't mean u have to do it also. i think it looks alright as it is. maybe her hand near her face could have the same value as her face.
also sometimes people say that using fewer colors is what painting people do anyway so mobile restrictions be damned. but they don't mention that painting people also sometimes just paint whatever color it should be. here's something i read: "Another method is to use a “limited palette”, where they might have only two or three colors of pigment and force themselves to paint their image with only combination of those colors. ... Not paying attention to this concept (which I rarely do) is called using “local” color… meaning the natural color of an object unmodified by the light, shadow or any other influence from around it." www.tomrichmond.com/blog/page/2/
In theory you can't have "too many colors" nowadays as we don't have the same restrictions as in the old days. Still it's advisable for pixel artists to use as few colors as possible:
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Yes of course! but it might look even better with less, I think. Maybe. 
too many colours? im confused, cant i have as many as i want?
Yowza, that sure is a lot of colors!
Pare them down a little, maybe? A lot of themare so similar that they're hard to distinguish.
Thisis a charming little sprite, though! I like the way her feet are turned in like that, it's so cute.
It's cute!
There are too many colors though (38+transp), 16 should be more than enough and would make it look cleaner.
The arms are too dark, look a bit dirty.
And, welcome!
Edit: I like the av and banner on your website, keep'em coming!
Very cute. Very readable for a small size.
As far as color counts go. A lot of times more colors will make it look smoother like a higher resolution..at least that's what I find. It depends on what it is though and the style. This looks great though.