Alright, this happened to me over the Summer. I went to one Doctor, and they said that I had an ear infection and put me on antibiotics for a week. Still happened, so I went to another Doctor, and it was just wax buildup from wearing headphones playing games, earbuds, music etc. They flush your ear out in like 3 minutes and your hearing comes back. I'd personally just go to the doctor now because it's a waste to do it yourself. Oh, and cotton swabs aren't for cleaning your ear out. They push all the wax back further and make your problem worse. Doctor.