Is white blood cell count of 12.89 aftr laparoscopic total hysterectomy bilateral salpingectomy and removal of i ovary because of cyst mean infection?

No. An isolated: number means nothing. There are a number of causes for elevated white blood cell count and yours is just barely at the high end of normal depending upon your lab. Infection is a clinical, not laboratory (usually) diagnosis. Use your head, if you feel sick then perhaps you should see, or at least call the operating surgeon instead of posing an unanswerable question to doctors you don't know.