Liquid levels would be parallel to the horizon. Look at liquid level in glass at far right for comparison.

Fixed source 2.

@ CMYK46: It depends on the thickness of the matter in question. I agree the closest glass should probably have the liquid inside more inclined to the left if it was water or wine.
I give you some reasons for the levels to do not look real in this case:
1. Even on the source picture you can see the red glass has a fixed material inside, couldn't this be the case? :P
2. It's even true blue which makes you think it's some sort of non real material or perhaps a blue jelly?
3. The glasses could be moving a little as she steps in and out which would affect the levels at the moment she does.

I'm not trying to excuse my supposedly mistake but in fantasy art what's real and not is relative. If you had picked on the shadows i would totally agree.

Good work !

very nice!

good job, but glasses look flat, maybe try to add some thickness to the edges of the glasses or maybe more shading on the empty part of the glasses, good luck

EDIT: also the glass in the front should drop shadow on the glass in the background.

Congrats on 3rd

congrats