My Fiance and I are always at it...?

WE agreed that we would start making wedding plans a couple of weeks ago after being together for 8 years and having a child, so I did, I began, and now it's like we don't get along, everyday there is literally something to argue about he irritates the shyt out of me and he's making not be able to stand him, I don't know what's going on but it's detrimental to our relationship What is this feeling? I feel like there are two negative signs about our head like the Sims..wtf?