Sometimes @ night, i wake up & feel like 1 ear is clogged.i can tilt my head and it will drain some liquid.after that it's unclogged. what's going on?

Wax: Most likely wax. Water may be accumulating behind and around the wax after a shower and drains later at night. Nevertheless, you need to make sure that there no rupture of the TM causing an otitis media with drainage.

Water in your ear: If you are constantly draining liquid from your ear, you must find out if it is liquid that is coming from your middle ear through a ruptured ear drum or it is residual water from taking a shower, swimming etc. or even an infection of the external canal. It is worth a trip to your doctor to evaluate what is draining.

Multiple causes: The most likely cause of this is wax. Still, you may have fluid in your ear or other things. You can see your primary or ent, but if you do have fluid in only one ear, you should see an ent