He took my position

About six months ago i started working at a retirement village and or nursing home, I decided, after working a certain floor for some time that i would like to be a perm over there. I put my perm paper in and gave it to the Director of Nursing for her to sign. She did and as of yesterday i was supposed to start as a perm on that floor, i was so excited I love that floor and all my patients on it. I had one of my co-workers come up and ask me friday if i had put in my perm paper and i said yeh the boss just has to sign it. (Mind you he has been there longer then me but was pulled off his perm floor for abuse and is a float now). he then goes on to tell me..."well what if i just get infront of you and have my paper signed and take your perm spot away..how would you like that?"...and what do you know as of yesterday i was called into the supervisors office and told that i no longer had my perm spot because of him.!!!!
I dont know how to handle it i have worked so hard to get that spot and now it was just taken away...what can i do? i have done nothing but cry and complain since yesterday evening!!!1