cope with my A.D.D.

I am SO random. I’ll be in class, and my teacher will be like “Nicole, could you explain to us how your heart pumps blood throughout the body” and I’d be like .. just talkin’ away about how it goes through all the chambers, and how it gets pumped through the different arteries, then I’ll go “OMG LAST NIGHT I WAS TALKING ON THE PHONE AND YOU KNOW WHAT NATE SAID? OMG IT WAS SO FUNNY” and I’ll start talking about something TOTALLY different. My mom says that I don’t have A.D.D. I just need to settle down sometimes, but I think that’s just an excuse for her not to have to deal with it. My mind races really crazily too. I’ll be driving down the road, and I’ll see a box on the side of the road, out of no where, questions start flowing through my head—“How did that box get there?” “Who did that box belong to before?” “Did someone PUT it there, or did it fall out of something?” “What did it used to have in it?” “Why is it there?” just.. about.. a STUPID box, let alone the many other things I see and wonder thousands of questions. My teacher said I over exagerate, but I don’t think I do, I seriously think its because my mind is so crazy and everything seems like 20 x more extreme to me, than it really is. Does anyone know how I could deal with this? Maybe it’s not A.D.D. maybe it’s something else, or I need to stop eating so much candy. I really don’t know, I just know that sometimes I get SO overwhelmed because of this.