Help!Question.

Guys I got a problem!..

I brought my 99Gt to ford..I have a feeling the switched my headlight!
They were a brand new set ( smoked ) When I got it back from a clutch job the headlight started fogging up all of a sudden. They never did that before! I sure they switch it with another!! How can I tell they did it? Any #'s should match or something...Thanks for the help