Is it normal to be cold after surgery?

I had a bilateral tissue and nipple sparing mastectomy with immediate reconstruction on June 8th. At that time they placed my silicone implants. I have been cold ever since. My first thought was that I was running a fever, so I have been monitoring my temperature ever since surgery. My temp has stayed right around 97. Yesterday was the first day I actually go hot and it was 94! Is this normal after having surgery?