I agree with the pseudoephedrine suggestion, and also some type of nasal spray that helps to clear your sinuses. An RN friend suggested that when I flew in April with a head cold and I was fine. I used the nose spray in-flight (in the restroom) about an hour before landing.
Just be sure it is a small bottle of nose spray, since it is a liquid and will have to go into your quart-size ziplock bag for security screening.
My sons ears got that plugged feeling (and he hadn't had a cold) during landing, but the pseudophedrine helped him out later that afternoon too.