I typically have a very low cortisol level despite extreme physical stress of disabling illness for many years, multiple surgeries, and injuries. Then this year cortisol level very abn. high with no unusual stress. At the same time my RT3 level high( I am hypothyroid as well as PCOS). Then body crashed weak as can be. Then fevers and glucose all over the place. It took 9 months of me pushing the Drs and a week in the hospital for them to find blood infection causing this. As soon as treated then I had to change thyroid medication to reduce the RT3 caused by the situation. This was making me just as sick no improvement till I did .I had to go on a T3 only medication to get it out of my system but then the cortisol level started to normalize finally.
If your cortisol is really high, look for an illness that could be causing the reaction. I would hate for you to go through what I have. And realize one thing will get something else out of whack. I had been through as much stress as possible and cortisol never went up to high level till an underlying condition caused it.
Friendly Input from one who just went through this and still working on. It has been a struggle but I have had to be the Dr in this one to lead them to the answers because my health so complicated. It could just be be emotional stress- but it never did for me. GOOD LUCK TO YOU!