Legs suddenly itch, asthma/allergies?

I was working out in my house today on a hardwood floor, and about 10 mins into the workout I noticed that my legs started itching, pretty badly. I continued working out, and after I was done they still itched a little, and about 20 mins afterwards I started having a little trouble breathing (I have asthma). Does this sound like an allergic reaction to something in the house, like dust or mold?