I would be interested to learn why you had a breast reduction (it does not sound like you had a breast 'lift' or mastopexy) in the first place?
Certainly with size 'G' breasts, you might have had neck and back pain, posture problems or hygeine issues. If this was the case, have these troublesome symptoms resolved? If they have, then you achieved one of the important goals of the procedure, and that something to be happy about!
As far as the breast size reduction, you insurance carrier might have 'demanded' that a certain minimum amount of tissue be removed during your breast reduction. This is a common demand by third party payors. At times, it's challenging to safely remove the amount of breast tissue that the insurance company requires, but in other cases, it's not a problem. Your surgeon cannot remove all of the tissue that is available to be removed, since the blood supply to the remaining breast skin and nipple must be preserved.
If your insurance company paid for your breast reduction, that may explain why your surgeon removed the amount of tissue that he/she did.
Frankly, a 36D size, if that is what you truly are, is not 'so small', but size is in the eye of the beholder, correct?
It's my feeling that third party payors set the 'required' amount of breast tissue to be removed on the 'high' side, thus preventing a subset of patients that really need the procedure but fall under the resection requirement, from getting the procedure. Insurance companies don't want to pay for surgery and they do not have your health in mind when they authorize or decline to pay for a procedure.
The sooner the public comes to grip with this fact, the sooner appropriate reforms will be made in our ridiculous health care delivery system.