Hawkins is minus the fee he paid the doctor, but being minus the fee is not a result of the breach. He would have paid the fee even if the doctor had not breached his promise.
The fee does not get included when we determine the position Hawkins is in as a result of the breach.
Hawkins gets the difference in value (measured in money) between having a perfect hand and having a hairy ugly hand that is a constant embarrassment and makes it difficult to get a job.
That puts him in as good a position as he would have been if the doctor had kept his promise. If we award the fee too, we put Hawkins in a better position than he would have been if the doctor had kept his promise.