I'm also wondering if it could have been from a previous client--I noticed a smoke smell in my T's office last week, but I know he doesn't smoke--I assumed his last client was a smoker, so the smell rubbed off on something in the room.

I'd say something to your T--just mention the smoky smell (don't accuse her of smoking) and see if maybe she could bring in an air purifier to run so that you're comfortable. If it is a client, maybe you could switch times or days (or see if she can have that person switch so it doesn't smell in the office?)