I would be persistent with your doctor about being evaluated for ADHD or ADD. I was missed as a child with ADHD and only got diagnosed 10 months ago. I am now 57. So it is never too late to find what is wrong and there are options for you. You have to be persistent if the condition was missed in childhood. I found that out. I would get a doctor who will listen to your problems and be ready to explain your problems in school when you were younger as ADHD starts in childhood as you stated. Hope that this helps and good luck.