you're not going to feel full on liquids. They go right through you.
in addition, you're very early out. Some of your nerves have been cut, and it takes awhile for them to regenerate. So your brain and stomach aren't "talking" yet - you're not going to get full signals right away.
you should start feeling restriction once you move to solid foods. Those DON'T go right through you - they'll sit in your stomach for awhile - and also, by then your nerves will have started to regenerate.
also, keep in mind for the future that often "full" signals are different after surgery than they are before. It can take awhile to figure out what yours are. I don't feel "full" the same way i did before surgery. Now, I just feel an uncomfortable pressure in my chest. I've learned if I don't stop eating when i start feeling that, I'm likely to get sick. Other people have reported things like sneezing or hiccups when they've reached that point. But for now, being on liquids (and soon, purees), you're not going to have to worry about this - you're not likely to feel anything because of the nerve issue and the fact those things go right through you.