Re: Can anyone give me some advice?!

Sorry to hear you're feeling so rough...i hope this passes quickly for you.

I guess with your high stress life, then your hike, you've pushed your body to the limits and it's crashing due to 'X'.

My boyfriend went to Peru area and he didn't get unwell while there but after returning he came down with similar symptoms to you, akin to dyssentry coupled with flu. As malaria has been ruled-out in your case, it could be a bacterial intestinal thing.
With diarrhea and vomiting we lose so much fluid and minerals that blood pressure gets affected causing dizziness, nausea.

With perhaps your normal state of being fight/flight coupled with an infection could easily result in a 'crash' type episode.

It's best to rest and fluid-up as you say you're doing and wait it out. Up your Vit C intake of course, and have good electrolyte broths/ Sea Salt to replace what you're losing

It could easily be an episode which passes so try not to think the worst. Theoretically, if you were able to mentally and physically cope with doing the travelling and charity hike you were in good condition, and as you didn't mention having these type of symptoms before going, it would seem as you've got into the swing of being home again and into normal routine of daily high stress, raising cortisol (suppressing immune function) has allowed latent bacteria (from your trip) in your system to get a foot-hold and show symptoms.

Normally people report with adrenal/thryoid issues of having mild symptoms and then other ones coming in, then a worsening of symptoms. You've described it as being quite an acute onset of awful symptoms, and as you've been to foreign lands, it sounds bacterial.

I hope you get your strength back soon. If it persists obviously consult with your doctor again.
Be mindful of the normal day stress you have. Try to limit it as much as possible. Most folk here talk of the high stress life before endocrine issues and it's a disaster waiting to happen to keep driving the body and mind 100 miles an hour.

I was like you, loving the pressure and adrenaline rush of life...i couldn't get enough! My inner voice kept telling me to slow down but ignored it, for years. I wish i had listened now, as it's been a wild ride of hormonal disruption and all that comes with it.
Now im more chilled...sure i have concerns, worries that fleet by my existence but if something doesn't get done, i let it go, knowing it actually doesn't matter, in the grand scheme of things.
It's hard to change habits of a lifetime, but slowing down life to heal and being in the pit of hormone hell has been a blessing to show me that i don't need to be a driven maniac ALL the time and there is a 'Zen' person in me that floats through life.

Hugs for a speedy recovery :-)