Do not worry. There was nothing you could do to prevent the scar and if it did not happen you would not be here ... or your Mom
Our first very ferret was named 'Tickle'. It stood for 'Tail-Less Ice Cream Lover'.
We got a deal on her because she was tail-less -- when she was born, her mother accidentally chewed off her tail trying to chew her umbilical cord. Some scars last a life time.
That mama ferret was stressed.