Many people who start medication therapies to treat the core ADD/ADHD symptom notice subtle changes that are not always easy to accept or manage. The character style that was considered to be a problem is now dearly missed! You were always entertaining, funny, jumped from topic to topic and never at loss for words and now after therapy with ADD medications are concentrating much better but feel awkward in conversations especially with people who know you well. This effect could be so dramatic that some have reported to me that their coworkers demand that they go back to their previous 'life of the party' selves! So here are some suggestions:

Acknowledge that you are not diseased but are managing aspects of your behavior to fit your life style and daily demands
You can adjust the dose of your medicines with close supervision of you doctor. Be sure to tell her about the subtle changes in your personality and your concerns and expectations. 
Adopt a role of an observer of yourself; you will be able to modify your behavioral habits slowly over time ; that's rewarding and liberating
Stop being so hard on yourself; what you consider a 'problem' is most probably unnoticed by most people. People have their own problems!