What is happening?!

Ashley
These past few days have been horrific! 
I have no idea what's wrong with me! I started my period yesterday. When I started, I had chronic back pain and cramping, and my head started hurting beyond belief!
My head hurt all day yesterday, all I did was lay in bed. No blankets, no clothes, sweating like crazy! 
Today, so far the same thing! Laying in bed, no clothes, horrific fever and sweating. 
I have been drinking as much water as my body let's me. Every time I drink my body threatens to throw it all up. 
This. Is. Horrible.