J.P.
I did this also when I was around two. I was one of
five children, all one year apart. I was 4th born
and the only one with this particular habit.
I had a perfectly healthy family life with "the perfect
family" intact. My head was shaved and by the time it
grew back, I was out of the habit. My mother put me in
very feminine clothes so that I would look like a girl.
Today, a grandmother, I am still very laid back,
no anxiety in my past. Hope this helps. Good luck.