vyvanse works not long enough and not every day

just got switched to 70 mg vyvanse from ir cause i was sick of the rollercoaster ride every day up dow up down it was exhausting and i was very irratable.  the first few days i thought i finally found what i was looking for but then it started crapping out on me early afternoon.  i still have ir ive been taking but i was wondering what one is the best to go with it id ask my dr but i honestly dont think he knows it seems to be a guessing game.  IM 30 and have been on all add meds over the years never commiting to them the best i did was on adderall (adderrall) when i was 15 but i quit taking it for some reason.  I tried it again a couple months ago and it was complete garbage made me super depressed i look like i just shot heroin and i had to go to the hospitol not to mention it was expensive for a sugar pill so i wont try that again i was on desoxyn when i was a kid too does the same thing happen with that or does it still work i have zero faith in generic drugs they say they are the same but they are different colers so right there you know its not the exact same formula i broke out in a rash once.  anyone that expierienced this i need some suggestions i have a dr appt next week and dont know what hell do probly get me even more messed up than i already am thanks for any suggestions that worked for you.