Why do I have water in my ears?

And how do I get rid of it? I had a cold a couple of weeks ago. It came with a bunch of congestion and snot. Well, I got over the cold in the usual time, but here I am, 2 weeks later, long after all the symptoms disappeared, and suddenly there is water trapped in my ears! It’s been there about 4 days now. I can feel it and hear it, and it’s affecting my balance.
How do I make it go away?
I tried putting mineral oil in my ears but, duh, oil floats on water so that did no good at all.