Adderall xr vs phentermine

Patient: I was previously on adderall for over 8 years and i stopped taking it at 19. im 28 and have weight problems now so my doc put me on phentermine. Im on my 6th day and it hasnt done anything at all.. do i have a tolerance for it??? it makes me sleepy

Symptoms: Sleepy, very calm the same affects adderall xr had on me…. i dont eat as much but it doesnt give me energy