Dear Chery, hello
The swelling on your head can be a lipoma i.e. a benign tumor
of soft tissue
consisting of fatty or adipose tissue
. Please check whether it is movable or not.
are soft to touch, usually movable and generaly painless.
Usually treatment of lipoma is not necessary unless they become painful or movement is restricted.
It is advisable that you get yorself medically examined. Treatment of lipomas is excision.
I hope this is useful to you.