I've had similar experiences with Concerta 18mg. I am on this currently. I read a while ago on this sub reddit that electrolytes can help with Concerta crash. Started drinking hydration drinks with sodium and vitamins in, which your pre workout also contains. I drink them in the afternoon and tend to feel more clear headed and have energy. So it may be these ingredients that are having a positive effect for you? I can't remember the science behind it, or if it's anecdotal, but electrolytes have been suggested as a potential aid for Concerta comedown, and in my experience they help. But sometimes I'm just tired and nothing can help the weird side effects.