What a bum deal ! I assume staying as a probationary employee leaves you without benefits? Do you have peperwork from them stating you were hired with a 3 month probabtion period? If you do, I would make appt with head of HR , take your paperwork and have a little talk ! This is unfair to anyone who goes to work there ! About the anger - I have found it helpful to write whoever I am angry at a letter........spill your heart out. Then burn the letter. Just to get it outta your system. Journaling is a good way to help get emotions out in a safe way as well.

Good luck ! Sorry you are dealing with unfair employer!!!!!!