Am i entitled to a refund from my attorney if i was never charged?

if i hired a criminal defense lawyer after an arrest expecting to be charged with felonies, but was never charged, do i get a refund of some of the money? the retainer was 7500 for a federal case, but charges were never filed, and the only work the attorney did was accompany me for dna testing, and some minor correspondence with the prosecutor and the detectives. does this entitle me to a refund of some of the 7500? i never signed any paperwork saying that this money was non refundable.