Just wondering, do you have carpet in your apartment? When I was younger, I had a lot of allergy and breathing issues. We had a dog and the doctor thought we shouldn't have one, due to my issues. Instead, my parents took up all the carpet in the house. This didn't cure me, but it made a drastic difference. I still have dogs to this day and, as long as I vacuum/sweep often and have no carpet, I'm able to live with them no problem
Just an idea!