Heatmiser, you should see your DR to discuss asthma. I don't think it's something that you can diagnose over the phone. It took a couple of years of spring time coughing for me to get diagnosed finally, and that came about when I woke up at 2 am feeling like my husband was sitting on my chest (he wasn't, LOL!). Asthma is an inflammatory response, and like your Crohn's, can get totally out of control if it is not treated.
Maintenance meds are necessary because most people become tolerant of the rescue inhalers pretty fast. You cannot use albuterol every 4 hours and expect to be able to breath well after the first day or so of that. A steroid inhaler reduces the histamine response to whatever is triggering your asthma and reduces or eliminates your need for albuterol.
48 yrs old, IBD diagnosis in spring '01. Proctitis, gastritis, ileitis.
Currently taking Pentasa (3g/day), Sulfazine (1.5 g/day), Prevacid, folic acid, vit. D (2K iu), flax seed oil (2 tsp/day), mesalamine enema as needed.