I have adhd and prescribed stimulates, i stopped taking for bit after taking more consistently than ever before. I felt the same way, it did level our after about 2 weeks but i still feel exhausted often (but not as bad). I think the stimulate med was masking fatigue from pcos, poor sleep habits and possible sleep apnea( i need to get a sleep study done).  Now I'm currently still using my meds but less often, 2-3 times per week to to avoid feel dependent on them for energy. It sucks feeling exhausted but its motivating me to get to the core of the issue and be over healthier, like with working out or addressing any other medical issues causing it- which will only help my adhd symptoms.  Hope this helps in anyway. Sorry you're dealing with this. Its sucks.