In order to rule it out or get a diagnosis, you would have to talk to a professional. If you click on "quizzes" up above, you will find a screening tool for ADD. Maybe that will be useful to you. I think that any time you are concerned about any symptoms you have, or they are causing difficulty in your life and ability to do the things you want to do, it is a good idea to talk to someone about it. Besides the concentration difficulties, you are also describing some perfomance related anxiety, so you might want to look into things like Social Anxiety as well as ADD. A lot of people meet the criteria for things like this but are able to function in life well enough that they are not aware of having any kind of disorder. Maybe their natural coping skills are good enough that they don't really need treatment. It sounds like you have done ok with your life so far, but maybe medication and/or training in social skills and stragegies for better concentration (which are included in therapy - individual or group), could help you to get more out of life.

<font color=orange>"Never forget: 2 + 2 = 5 for extremely large values of 2."</font color=orange>