My body is getting hot and i have a fever after working out. Whats wrong with me.?

Ive been going to the gym for years. Most recently i went to the gym and Burned a total of 2000 Calories, Something which i have done before. After my first 1000 Calories i had a juice, Post 2000 Calories i had a protein shake followed by a chicken salad. After i got home i was feeling super hot from climbing stairs. So i started guzzling another 2L. My body didnt finally cool down till 330am. This was yesterday. Today i feel feverish so i drank a lot of water some vitamin C and a Fever Reducer pill. Now as i am typing this message i am getting rashes on my body, WTF is going on with me! I am so not headed to the Gym today.!