Thank you all for your replies. In some way it feels good to know that I'm not the only one with this problem, however of course I'm not happy that others are suffering too... a great paradox I assume.
However, yesterday I went to see a ENT-specialist who by camera (or a small snake-looking devise) could see that the passage through the nose to the sinuses was swollen. So now I'm on cortison for six-months (!!!!!!) and some other kind of medication (de-swollowing). Sorry for my crap english medical terms. Tuesday I'm of to Paris and I am very curious/apprehensive on to what to expect when we start to descent...
Once again, thank you for taking your time to reply on my issue.