What cause inner ear infection?

Two years ago, I had gone to the doctor because I be feeling unbelievably nauseous and be feeling dizzy similar to vehicle or plane sick and was given antibiotics and recovered. At the time, the doctor didn't really clarify how inner ear infection occur. Just mentioned that our "ears" keep our body hanging. Recently, I began to surface dizzy and today I started feeling a bit unsettled and I feel tired only sitting on the couch. I'm in my mid-20's, a tough person and hadn't caught a flu for a long time. Can someone explain to me how inner ear infection occur?What cause inner ear infection?
Sometimes water can procure trapped in the inner ear strait by either swimming or when you lug a shower. The trapped moisture causes microbes to develop which then creates glow and swelling of the eustacean tube (the mechanism for balance). Check the site below for more information.
own you checked for sinus problems? Itchy throat,coughing watery eyes? Its allergy season too. I get my ear infection from my sinuses, I had it for a month, the ear drops I get costed 40.00 bucks from the Dr, expensive but it work or you can do over the counter ones.
It could be from getting water contained by your ears if you swim a lot. Also if you hold sinus issues and/or blow your nose tricky, it can force the mucous into your eustachian tubes and cause infections.