T.R.
I suggest having his doctor check his ears for an ear infection. It is normal for kids who have ear infections to wake up crying and not want to take sippy cups. It hurts them to create suction and lying down causes added pressure & pain. They say the pain comes in waves. And nap time/bed time is always the worst time of day.
My little guy is the same age and has one ear infection on top of another... and this sounds like it to me.
T.