ADHD Tips

I am 18 and have trouble handling stress, it is affecting my job and life. I have ADHD but I don’t know if this is a symptom of it or another issue such as anxiety.

As you must have known now that ADHD is characterized by hyperactivity (e.g. being too active, being fidgety, talking too much, being restless, or having your mind be always racing with thoughts); inattentiveness (e.g. difficulty paying attention, mind wandering, forgetting or losing things); and impulsivity (e.g. acting first without thinking, interrupting others, not thinking about the consequences of your words or actions. You just have to develop tactics/techniques to manage stress, as with ADHD, most find it difficult to handle stress. You must take advice of your Dr, how to handle stress, may be he can refer you cognitive behavioral therapy.
Besides, on your part whenever you feel stressful, try to get involve in those activities/stuff that make your thoughts deviate, or feel you relaxed & joyful. Share time with others, even talk to others about your problems whom you trust. It would definitely help out relieve from stress to some extent. Also, read these articles here on Teens having ADHD and different problem they face, I hope it helps.