Hi, I have been working out for a long time, and I have never gotten these symptoms before, towards the end of the workout I get the chills, on my arms my hair sticks up and I get little colorless goose bumps on the backs of my arms which are cold and when I touch them i get a very sharp shock, its very stiff and painful. Also sometimes when i wake up during the night i have very bad joint pain in my elbows and knees, I am only 19 so I dont know why this is happening. Please help, Thank you.