I do have one thing to say though
Next time try to make the belly more even to ensure the proper roundness this is important as you will end up with what I like to call the oval belly and the oval belly never looks right.
and for liquid/water inflation apply a slight sag to show it's a liquid or water not something like helium or air.
you can learn from this tutorial here as well:
http://www.furaffinity.net/view/6461730/
And don't worry tutorials are made for copying that's how you learn.
just make sure if you use someone else's art as a base you ask first.
I hope what I say helps.