That's perfectly fine to drink the shake in 30 minutes. The swelling in your stomach has gone down and allows the liquid to pass right through. However, you now have absolutely no excuse not to get your water in every day! You won't really start feeling restriction until you start eating soft foods That's also when you start being able to feel "full".
One tip for the hunger: Sugar-free jello, DON'T CHEW IT WELL! It will be slippery enough to get into your stomach all right, but it will take your stomach a while to break it down, so you feel full for a while. The little ready-to-eat cup is the perfect size!
Good luck!
p.s. In my area, bariatric support meetings are open to everyone, even if you didn't have surgery at their facility. Maybe you can find one near you?