I got that when i was on the plane. I had a bit of a cold and plugged my nose and blew to equalise the pressure. It worked on the first descent, not on the second. It hurt like hell. I used one of those nasal decongestants for a week or two. That's about how long it took to clear. The hot water bottle would help, too. If it does get worse, that might be a sign of infection, and then antibiotics would be the next step.
S