Open Question: When will Chickenpox fever go away and how do you count the first day you got chickenpox?

I'm 16 this year, this is the 2nd time I got infected with chickenpox and I've never felt as sick as this. Last Thursday, I started getting slight headache so I thought it's just some normal flu. On Friday, headache still persist with an addition of slight fever and a few spots of chickenpox. On Saturday, my doctor confirmed I got infected by chickenpox. After that, rashes and spots kept on