Thank you for the query.
This lump can be soft tissues swelling or (most likely) blood collection in the soft tissues of the head. Such blood collection, when is long enough can get infected and became an abscess
. Abscess gives plenty of pain, the skin gets red and swollen in its area. Every abscess should be drained as it is a potential risk of whole body infection.
That is why I suggest you to visit your doctor again and have it verified. In case of doubts, soft tissues ultrasound
should tell if there is any fluid or not. Small incision and pus or blood drainage
might be necessary.
Hope this will help.