Please be careful in the future. While this artist seems to be stringing you along, if you commission future artists and they complete the work before you want the refund, most artists will want to be compensated for their time. $7 is no where near compensation for a completed $32 commission if they had completed it. Most artists would not refund you. If they had even half completed the work the artist would ussally keep some of the money.
I am sorry this happened though and I really hope it gets resolved.