Argentine girl asks for more money after 5 minutes

Talk about a bait and switch. I was told it would cost me a certain amount off the bat. Then 5 minutes in to a rather mediocre blowjob, she starts asking me for more money. This is when I should have got up and left, but she knew I was really horny at that point and needed to bust a nut, so I paid her what she wanted. I will not be a repeat customer though.