How do i resolve constant fighting wiht my girlfriend?

me and my girlfriend keep fighting constantly about things that we dont even know what they really are about. We have a little disagreement but then that continues to expand and we fihgt about why the other person is mad.. its probably cuz both of us are stubborn and we find faults in each other and we rly dont noe what to do after or how to resolve this cuz most of the fights are based on senseless arguments. Its little things like stuff she says or i say that normally would be fine but because we are dating they arent. not sure how to explain it. Can someone give me something to say to her or tell her in order to cease this fighting? thanks :)