Brett, Baking soda and vinegar are the ingredients for a gradeschool volcano!

Don't put those two in your ears. Like mentioned above, white vinegar and alcohol 50/50 is pretty much the same as the swimmers ear solution you buy in stores. Works well.
depoint50ae, the only way to get lake water in your middle ear (space behind the ear drum) is through a ruptured TM. Perhaps you could get a miniscule amount in there if you crashed with your mouth open and a little water got forced up your eustachian tube into the middle ear? Sooo, ear plugs and crashing with your mouth shut will prevent it.

You may have had water in your other sinus cavities that could make your ears feel full, blocked, or even some referred pain? You didn't have water in your inner ear. It can't get in there, only middle ear. Any traumatic disturbance of the inner ear would cause vertigo,nausea,tinnitus, and hearing loss. See ear diagram:
http://www.echalk.co.uk/Science/Biology/InteractiveDiagrams/ear_web.swf