Hi friend. We need to breakdown your query into points to have a clear understanding.
Braces do not have any effect on hair.
Teeth don't become loose normally. But if the dentist uses excessive forces to move the teeth or if you don't maintain proper hygiene then teeth may become mobile temporarily.
Earache and soreness of throat is not a direct effect of braces.
Next Steps
Regarding sore throat and earache, plz get yourself checked by a dentist to rule out the possibility of wisdom tooth problem which may cause earache. If that is ruled out, the you may see an ENT consultation.
Health Tips
The best way forward for you is to be expressive to the dentist. You must express all your fears to the dentist who is treating you so that your fears can be allayed. Hope that helps!