I discovered a lump on the top of my head. It is like as if I bumped my head and lump formed under the skull.  Any ideas as to what it could be.  Just had my hair dyed two days ago.  Could this have anything to do with causing the lump?  It is not painful.
Hello! Thank you for the query. Lump in such location is usually a sebaceous cyst. It grows spontaneously so you could not cause it. It is usually rounded, painless, with smooth surface lump. However, it can get infected and due to pus accumulation can be painful. I suggest you to consult a surgeon with this lump. In case of doubts, soft tissues' ultrasound can be done to determine what exactly it is. Cyst can be removed with small surgical procedure. Hope this will help. Regards.