What Causes High Fever Post A Surgery On The Index Finger?

My husband had surgery on his index finger yesterday after cutting it on a pipe. The doctor did a debridement of the wound and extensor tendon repair. We are 24 hours since the surgery and he is running a fever of 101.5. He was given I.V. Antibiotics during surgery. I called the surgeon and his on call doc told me that if he didn t have any redness or bleeding from the wound, the doctor wouldn t see him and we should contact our regular physician. Unfortunately it is 9pm on a Saturday and our physician is unavailable. our ER copy is $500, which I don t want to pay for them just to tell me to give him Tylenol. Im not sure what to do. He has no other symptoms except the fever.