Once In A While Out Of A Blue Moon, I

Once in a while out of a blue moon, I have this kind of cold attack. I happened at night and day time.My body felt a chill that forced me to put on socks, deep my cold hands in hot water, turn on the heater, drink a little bit of wine...and go to bed. I did not have fever, headache, pain. Just feeling very cold not only on my exterior body (skin) at I also tremble of cold I feel from the inside.
I am taking Losartan 25mg for blood pressure, had history of Thyroid dysfunction, and as a result half my thyroid has been removed. However my TSH is normal. My doctors did not suspect anything abnormal at this time. I have not talked to them about those irregular chill symptoms, thinking that they don't believe anything serious. I don't think I am anemic. I weigh 125lbs, do light exercises at the gym, at least 3 times weekly. It usually took me more than 3 hours to overcome these chills. What to do? What could be the cause of these symptoms? Any sickness?What treatment is needed?