Online tests are hard to gauge accuracy. But some of them are pretty good. The best thing to do is talk to your primary care doctor and get a referral to a psychiatrist. Only they will know for sure. Even with your history of addiction, if the psychiatrist does not want to give you a stimulant (can be addictive) there are non stimulant choices to treat ADHD/ADD. Good luck and keep us posted on how you make out. And congrats on taking the steps to further your education. I had untreated ADHD and managed to get through college somehow. I did well too.