Can hair just start popping out?

If you suddenly have hair loss after a vacation and have itching and tingly feeling on your scalp, see a doctor.  You may have an infection such as head lice or ring worms.  Otherwise it is just guesswork until you see a doctor.

Without seeing your scalp, one can't comment fully. There are many causes. Only a full history and up close exam can determine the cause. The most likely causes are traumatic breakage and extraction of follicles on account of the rubbing. Should this be the case, hair loss should be temporary. Whether you fully regain the original density you once had is hard to say (it depends on how much genetic hair loss one had to begin with). Other causes include infectious, inflammatory and hair loss from chemical irritants.  Further evaluation from a dermatologist is warranted if it does not improve.