Is my doctor supposed to tell me how many units he gave me?

Dr charges per area for dysport. I didn’t ask at the time how much he gave me. If I go to His nurse it’s per unit. I’m trying to decide whether to go to the nurse based on cost. Called office to ask how many units and they said they don’t give out that information. I asked why and reception said it’s in his head not in a chart front office can access. I asked if he charted it somewhere and she said yes only Dr and nurse can see it and when she asked Dr, he said they don’t give that info out