I had this issue when I tried to switch temp to another branch from the master branch and when I would change something on that temp page and without committing the changes I would checkout the master branch again, it actually merged all the changes from the TEMP branch into MASTER.
ANSWER:
Whenever you checkout to a TEMP branch, COMMIT your changes. That way if you commit them on the TEMP branch and checkout MASTER again, it will work as supposed.