Large soft spot on adult

I am a 52 year old adult female.  Last week when getting my hair done by a beautician she noticed a large soft spot on the top of my head.  It is about the size of the palm of my hand and feels mushy to the touch like its water or pus underneath.  I am not in pain, there is no visable scarring or bump.  I do have headaches peridically that are more like a shooting electrical shock wave that only last about 30 seconds but not everyday.  Unknown if that is related.  I had a complete hysterectomy 4-5 yrs ago but do not take hormones, I am on 3 high blood pressure meds and take meds vicadin, flexril, soma for a back injury.  Could the meds cause the soft spot? To my reluctance, I saw a doctor and he referred me to surgery and then they referred me for a CT Scan that I am awaiting a date.  I am very concerned and trying to figure this out before I get my CT scan and see a doctor but jumping all over the place from minor to very serious.... PLease help?  

[aamy007]

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