You are young now. If you don't get to the bottom of the stress and anxiety I fear your adrenals won't be able to pump out those levels of cortisol for many years.
I bet the next stage will be feeling amped up for days and then "crash" with fatigue, maybe catch a cold, etc. That is probably your body switching to low cortisol.
Ever try magnesium glycinate, glutamine and or GABA? There are plenty of other things to try as well.