I can't pop my ears...?

I traveled from Huancayo, Peru to Lima, Peru today. The trip reaches altitudes as high as 4500 meters (some 13000 feet) above sea level, and though I've made the trip many times and am used to the altitude, I have a mild cold and am pretty congested. I feel like I need to pop my left ear, but I can't. I can pop the right one, just not the left one. It's late, so I have to way to get a decongestant to help with it, and I need to fix this soon because we're traveling by plane in a few hours, and I know from experience that it will just get worse. Are there any other methods to get rid of this, or anything around the house that can work as a decongestant or to simply pop my ear?