What Causes Poor Concentration In An Adult?

I have been saying words that I don t mean to say in a sentence, like I love to bake clouds instead of I love to bake cookies. I have been doing it a lot lately and it s starting to bother me. On Thursday I took a news paper to a patient and said here is the Sunday paper. It was Thursday... I knew what day it was, why did I say Sunday? I cant seem to concentrate on things either.