Why are my braces hurting so much?!?

Got bottom in April and got top a month ago. Yesterday went to get my colors changed and they changed my wire. Its not supposed to hurt but on my right side of the mouth my braces are HURTING so badly i cant even eat and it hurts sometimes to talk. I took advil but that didnt work. My left side is completely great> My right is too tight i asked my dentist yesterday she said it would go away really soon. IT HURTS LIKE CRAZY! Any advice and when this will go away? Im leaving for europe tomorrow and i dont want this pain! x