It's probably worth pointing out here that the younger you are it's likely to be that the scalp numbness will sort itself within a matter of months. The older you are, it will take longer. A friend of mine who is 60 and has very long hair still has numbness in her scalp two years on.
Even among people of the same age it can, of course, vary from person to person. So be prepared for a long wait if you are older. Bear in mind, also, the numbness may never go away. So think very hard about messing about with your scalp, especially if you have a full head of hair and your hairline isn't too bad. I've noticed a lot of natal women have high hairlines, especially athletes who often seem to have their hair tied back a lot. Forehead feeling seems to return very much quicker no matter how old you are.
Caroline