The key to the proper use of antibiotics is to use them like a sharp-shooting rifle and avoid any blunderbuss approach. Easy to say but hard to do. You contributed to antibiotic resistance. It would and did. We call this antibiotic selection pressure.
Hospitals are the most common sites of antibiotic resistance development.
Environmental contamination takes place in Intensive Care Units where the concentration of patients, bacteria, antibodies and dirty hands is high, but problems exist throughout the hospital. Gonorrhea developed its resistance in the community. Oral intercourse prostitutes in the Far East have gonococci and meningitis causing meningococci in their throats at the same time. We pray that resistance to penicillin does not transfer by plasmids from the gonococci to the meningococci. Round, dark staining organisms, originally from the bowel called enterococci which can invade the blood stream, have successfully developed resistance to various antibiotics and are now only sensitive to vancomycin, an antibiotic that has to be given intravenously.