Hi. I sometimes get some unusual symptoms. If I workout too hard or exhaust myself in other ways (working in yard on hot sunny day, etc.), later in the evening I get intense chills (feel cold even with sweatpants and shirts and under blankets), cramping muscles and pain, can t sleep good, flu like symptoms. Within a few hours I get warm and start to sweat on and off and strip myself of my clothing. This type of intensity happens a couple times a year. But I have other more common, less intense symptoms a few times a month. No chills/feeling cold, but sore aching muscles, very bad sleep, headache; again after workouts or eating or drinking certain types of food drink (beers with hops/IPAs do it to me). FYI, I also have weird blood tests in the past 5 years where about once a year the results show my kidney functions dropping significantly, but when I go see a nephrologist they are pretty much back to normal. So they think that, even though I may have mild kidney disease, I m getting weird test results on occasion. I was looking through the internet today because I had one of those intense episodes with chills last night after working out intensely yesterday. I feel better today, but sort of like a mild hangover. A few years ago I played full court basketball with some young guys, and played intensely, and I had flu like symptoms for a few days.