I posted a couple of times here asking if I just had bad quality m or if I was creating tolerance, but I think what is happening is that I am ironically taking too much?

I am taking around 15mg with almost no tolerance (if my volumetric dosing is right). I get more functional for 1 hour, max 2. Then I feel what I thought it was a crash. But in reality I am trying to work badly but I feel unable to change whatever I am doing. Everytime I look at the clock, is way earlier than I thought, like time is not passing.

Now that I think about it I had the same on vyvanse: 2-3 hours of euphoria followed by this stuck feeling.

Is this because of a dose too high? It has to be right? the other day after I "crashed" I took an amph 2 hours after, and it just made the whole thing worse