I got a bad case of chills and related shaking in the hospital on the second day. I think it was a combination of lack of sleep, stress, anesthesia side effects, and stress. I experienced twice more in the subsequent days, but less and less. The Docs checked me for infection and there was none. I do agree, this is something you should contact your doctor for so they can check it out. But just to say, I had some rough cold chills and trembles during those first few days and now it appears to have receded. Good luck!