I'm 28 and have had asthma for a long time but a recent bout with broncitis has me currently using my inhaler quite often and it dosn't work as well as it used to. My doctor is thinking about getting me a portable nebulizer if this doesn't improve, and of course, in 3 weeks I will be on a plane to WDW so what happnes if I need a treatment on the plane and have to use the nebulizer? Is this allowed, or will I have to rely on my less helpful albuterol inhaler until we land?


Sounds like you've got everything all worked out.
I believe elcodfish has worked out a good strategy and should be OK. In a previous posts elcodfish decided to go with the portable neb which will be great for travel and can be used before flight, during a layover and immediately following the flight. Not to mention how much easier it will be to take into the parks. An inhaler will be kept handy on the flight as well. I do agree with the idea that a call to the airline in advance would be a good idea. As CleoPhad said, they may offer an alternative area to neb while in the air. In an emergency situation the flight attendants would have to be accommodating. 
