Postnasal drip for awhile. now its causing choking during the night.this week i now have sore throat dull head pain & dizziness. all related? cause?

Sinus infection: The head pain and dizziness suggest more than a typical upper respiratory infection. The post nasal drip could be draining from the sinuses as well. You might benefit from nasal saline rinses, a nasal spray like Nasonex (mometasone) or Flonase from a physician, and possible an antibiotic course. I'd talk to your physician about all of the above.