tats outstanding question?
if u think shaker is exp, then regular water bottle may work.
problems tat u could face are clumps in the shake (i.e bad mixing) and also it's harder to wash the water bottle if there is any traces in it (opening of regular bottle is generally smaller than the body).
if u insist not to buy shaker, drinking from regular cup/glass should b the best alternative.

DO NOT MIX HOT WATER WITH WHEY!!!
use cold water instead.

yes, definitely.
it's stuck at the bottom probably.