My adderal is making me tired...why? Iam I not really ADHD?

I was diagnosed ADHD about 4 years ago. I told my dr. we were trying to have kids so when he prescribed me adderal back then I refused because I was trying to conceive. Last week I went back and told him since I was now done with having children I would like to see if that was still an option. After being re-evaluated he disgnosed ADHD again but because nopw I struggle with higher than normal blood pressure he said he wants to start me off with a SUPER low dose for a month and then he will raise t if my BP is ok. 10 mg once a day. That's it. The first few days were ok...a little more focus but nothing like the "WOW" I was hoping for. Now I am on day 8 and I am simply......tired. I remembered to grab the hotdog buns WITHOUT my list the other day which is a new thing for me (LOL) but I am sleepy. Could I have been misdiagnosed TWICE? I wasn't expecting to want to take a nap in the middle of my day. I am usually on the GO GO GO GO and this is completely unpleasant for me. I have heard this happens to some but have never heard WHY? Anyone else?? THANKS IN ADVANCE!