I smell like paint.

No, that's not a euphemism for anything.  I legit smell like tempera paint.

I spent the evening painting set pieces for my roommate's musical. 

She teaches at a rich school.  She's their music and choir teacher.  Thus, she's doing a musical. 

And why I smell like paint.

I cannot imagine my kiddos in a musical.  But luckily I have my roommate's school to help prepare them to do middle class things - musicals and dances and actually having 2 specials instead of one....