Can anyone give me some advice?!

Can anyone help me find out what's wrong with me?! I have an extremely stressful lifestyle as a single mum with four small children running my own business. I regularly work 14 hour days and and am permanently living in 'flight or fight' mode - but have done for years and enjoy my life and its pressures most of the time and thrive off a certain amount of adrenaline and pressure.

I recently returned from a 10 day charity hike in Peru to raise funds for some local charities and threw myself straight back into working 7 day weeks to make up for what I had missed. I experienced severe altitude sickness during the climb but, stubborn a I am still managed to reach the summit and felt better on the descent.

I have been back for a month and felt great for the first 2 weeks (but knew I was working myself too hard) but in the third week I started with what I thought was a sickness bug. I worked through this (as is normal for me) but continued to deteriorate and the sickness and diarrhoea continued with more symptoms presenting.

I am now on day 15 and have had to take the past week off work (which I have never done before). I have been cleared for malaria which was the original worry and have been left to rest at home and let it run its course. I am keeping fluids and a certain amount of food down so the doctors are happy for me to stay at home unless I get worse.

My symptoms now are nausea, occasional vomiting alternating with diarrhoea, severe tiredness and weakness, salt cravings, dizziness when I try to stand, muscle pain, dull headaches which come and go, hot sweats and fever spikes, chills, my skin feels very strange and I just had a general feeling that something is wrong.

Does anyone have any advice? I have help from family and friends and the kids have been great bless them - I have never felt this poorly and I don't mind going through it if I know what it is and that it will improve over time but I look horrendously poorly and would feel better If I had some answers or advice!

Thanks in advance x