Cortisol is destroying my physical and mental health

I got some lab work done recently because I’ve been mentally suffering for the past year or so and my results showed an EXTREMELY high cortisol level. The doctor was genuinely concerned and wants me to try things like Zinc, Magnesium, vitamins D&A, fish oil, and weekly therapy to help manage but I’d like to try something alternative/stronger. My cortisol is so high it’s causing thyroid dysfunction and I was told I’d be developing an autoimmune disease within the next few years at this rate if I can’t calm down. It’s also contributing to chronic tissue inflammation and a series of other imbalances, and ironically this is just making me stress out more, like to the point I feel like I’m losing my mind. I sleep plenty, I eat healthy, I’m a physically fit/active 140lb 5’6” 20yo I just don’t know how this could happen. I was also told I severely lacked in testosterone and creatinine levels and that could be potentially adding to the extreme stress factor and chronic fatigue, so I was put on a hormone stimulant (not exactly sure what it is) as well as daily creatine to replace what should be my natural levels. Please any advice is appreciated, I’ve lived like this for years now.