Should X-ray Be Done In Case Of Severe Elbow Pain?

woke up 2 days ago w/ severe elbow pain, had to lift arm w/ other arm to avoid pain. just came from ER, doc only saw red elbow and gave rx for septra w/oo xray and w/o exam that shows wrist involvement. he said the nerve runs down the arm. should i have xray and manual exam before starting septra- i have a spint and sling. i 64 y.o. female w/ no history of arthritis but I thought this was severe arthritis or a fracture. thanks.