Is it normal to get into a heightened mental state after finishin exam

I've noticed that after I finish an exam, and I feel as though I've done a really good job of the exam, I get into a heightened mental state. In this state, ideas flow through my head faster than I can write them down (very creative and I'd describe them as possibly "visionary" ideas) and also I feel as though my mind is running on hyperspeed - I can formulate ideas faster in my head, I can make conclusions much quicker, etc.

It's not just my mind that feels accelerated - I have very high physical energy, like I run rather than walk because I'm so excited/exhilarated.

My thoughts are that it's normal, and that a high-stress situation which rapidly turns into a low-stress situation causes the brain to somehow go into hypomania/mania/euphoric/accelerated mode, or that perhaps I'm generally depressed/low energy and this combination of exam stress --> no stress causes my brain to function "normally" temporarily for a couple hours, until I come back down.

Do you think these mood swings right after exams are normal, and if or if not, why do you think they happen (if only to me)?