ive got a 7 month old male staffy. he is always chewing on things and making a mess which is making my mother wanting to get rid of him. also when it gets dark he always bites our feet and holds on to them. ive tried to make loud noises, firm no, redirecting him to somthing else to bite. could you please help me and give me some tips. if things still dont work out should i be taking it to obedience classes? will it cover my problems?