What Does Squishy Area On Head After Pulling The Hair Mean?

My brother (13yrs)suffers from a Mental disorder and can become violent when off his medication. He recently started to refuse to take the medications and his violence has increase.about a week and a half ago he attacked me and bit my shoulder and would not let go, so i tried to pull him off by his hair.he came to me yesterday and showed me his head is kinda squishy in that area. I am very worried and have made an appointment for first thing tomorrow but i was wondering if i should just take him into the hospital instead,and could this have been caused by hair pulling.