The one thing that is common among all the meds is if there's a song playing in my head. Wake up, random song in my head. Take my meds and notice sometime later that it's quiet. About the time the meds wear off there's a song again. Doesn't matter if it's methylphenidate, song about 4 hours later. Extended release song 8 hours later. Same with vyvanse.

The song can be anything today it was the mcu intro music. It could be a song from a commercial 30 years ago, or some earworm from one of my kids playlists or shows.

I'm currently in a month long lapse between meds, and it feels like "Flowers for Algernon" in my brain right now. Like, the sad second half. I used to be smart but now I'm not.

Anyway, when my meds wear off during the day, it feels like that but a lot less so. I can't wait to get my mind under control again.

Vyvanse (washed down with my morning coffee) around 8 hrs in I have a complete drop in energy and then about 2-3 hrs later I get a second wind.

It’s a challenge because I’m a couch potato for dinner time and then get things done when it’s time to wind down.

Depends on the meds. With Medikinet (methylphenidate, same compound as Ritalin or Concerta) it was like a hammer knocking me out twice a day, and feeling like a robot while its effect lasted.
Now I'm on Elvanse (lisdexamfetamine, same as Vyvanse) and the highs and lows are much less pronounced.
I don't even feel it directly, I just get more done during the day, am more patient and less anxious with it.
But long term I do notice that it also suppresses my other emotions, so I don't take it every day, especially not during the weekend or vacations.

Depends on the meds. For me Adderall gave me horrible crashes. Because of the side effects on appetite I would never eat or drink enough while on it, so when it wore off I just felt like shit. Tired, hungry, and distractable. With meds that work better for me I go from feeling productive and focused to feeling aimless and brainless, but without the physical issues of deprivation its not so bad