Then follow GD's advice in your other thread.
When I was young, I wasn't allowed to be outside after dusk due to asthma. My parents always kept the windows in the house closed, and my mother completely cleaned (including the walls) my bedroom at least once a week. I had it pretty bad when I was young. We had to give away my dog, too, lol.
Really watch your environmental factors.
I don't know if they still do it, but when I was young, I got some pin-prick test done to see what all I was allergic to. It was like a paint roller covered in little pins, each with a different allergen (cat har, dog hair, pollen, dust, et cetera) and the doctor rolled the thing straight down my back. It was actually kinda interesting, lol.