Adderall and Ritalin.. How do I address my doctor without him thinking im trying to get high?

Hi im 18 and I have a good deal of the symptoms of ADD and suffer from depression. I would like to be prescribed adderall because i have taken it in the past on one occasion without a prescription from a friend but only took 10mg of the adderall XR. I wouldn't abuse the prescription if i had it but I do know that it helped me focus and helped me stay content with myself. My main symptoms are trouble going to sleep.. I can lay down for hours with my eyes closed trying not to think and cant sleep. I also cant pay attention in cl because I cant help but listen to any words I can hear other people saying. The last main symptom that is holding me back is no matter how good things are going for me I cant find myself happy or motivated although im not a lazy person and have nothing to be down about... I really believe I need it and for the right reason I just dont know how to say it without my doctor taking it the wrong way.