Strattera and ADD vs ADHD | ADHD Information

I've been taking Stratterra for 12 days, and I can't say I've seen a bit of improvement with being unable to concentrate on or accomplish anything.  I'm taking 40mg twice a day.  Is anyone else taking it more than once a day?  I've also felt much more tired lately than I usually do.  My big question is since everyone classifies ADD and ADHD differently, is Strattera meant to treat ADD without hyperactivity as well as ADHD?  I rarely am hyper or excited about anything, so I'm wondering if this drug is even meant to treat what I have.