Is it possible for my 1 week old to forget how to latch on?

I thought that me and my week old son had the latching on process down pack but yesterday we started running into some problems. For the past week he was latching on great and didnt have any problems when all of a sudden yesterday it is taking us 15-20 just to get him to latch on. Its like he forgot how to latch on. When he was 3 days we gave him a pacifier and i was wondering if mabey this could be the cause of the problem? Could he be getting this confused with the nipple? or this just normal? If anyone has any advice on why we suddenly ran into problems please share your info.. Thank you in advance.