you should not have left until you got her name and badge id. you should have demanded to talk to her supervisor. i dont know why we get so timid and scared of these people. yes we look different and may have accent but legally we have the same rights as permanent residents and naturalized citizens. if you do not want this to happen to yourself or some other fellow nepali, please do everything you can to contact USCIS and report this issue. they did it to you, it will happen to someone else if you dont take action.