I have been on adderall for adult ADHD for 2 years bc after 5 years and 6 different anti-depressants my dr. thought it would help- which it did tremendously---today I woke up took my 20mg tab and was ok, then started feeling heavy and sluggish- so I took 40mg;....which only made it worse and then by 9 pm I could barely get up the steps to get in the bed! Please help! Is something wrong with me or do I need to change my dosage? Why would I have extreme muscle fatique and soreness? Walking up the steps made them ache and heavy--and yes I am a healthy 29 yr old.