It is uncommon to have a tumor to grow in just 1 day. Therefore, it is not likely a malignant tumor. I guess it may be infected sebaceous cyst or lymph node. It is important to look and feel the mass before making a diagnosis, so please go to your family doctor to inspect the mass first and provide appropriate management to you.
regards, Dr. Lai Wai Wah PGDipMSM (Otago), Postgraduate Diploma of Musculoskeletal Medicine (Otago) FHKAM (FM), Specialist in Family Medicine