It is recommended to call the doctor when frequently starting noticing the symptoms described above. Neglecting them can lead to a serious damage of the nerve over time.
The doctor will be able to suspect the trouble from the first examination.
Besides verifying the moments when symptoms appear and their exact location (i.e. if the little finger is involved this means it is not carpal tunnel syndrome), he will decide whether or not to test fingers sensitivity; moreover by flexing or pressing the wrist he will better understand the situation.