Do I have ADD or am I just a sped?

When I was in math cl I could never understand what was being taught. I had to just copy everything off the chalkboard and then I would figure it out on my own afterwards. How come I was smart enough to basically teach myself but I wasn't smart enough to learn it from the teacher. The weird thing is, I did better than my cl mates. It's like I am slightly above average intelligence but a very slow learner, or is that a complete contradiction?