work rant

I work per diem.  Know what that is?  It means "per day".  Yeh.  But I am not an "agency" nurse.  I am an employee of the hospital.  I am really appreciated by my coworkers and patients.  Especially my coworkers.  They are soooo glad to see me.  And now, during the holidays, I am almost working full time so everyone else can take time off.  Am I nice?  NOT!  I have been very grumpy and bitchy.  I found out about an hour before I left work tonight that I have to work Monday.  What?  The other nurses were kidding with me about talking me into working Monday, and I said there was nothing that could get me there, I refuse!  Then, they showed me the schedule.  How did I miss that?????  I am working so much now that they depend on me, which, in its own way, is sorta nice.  But, now that they treat me like regular staff, I also get the shaft just like the others.  I get crappy assignments.  I end up staying late to just get done.  Trying to ask for help is useless.  Patients think I am a "senior" nurse, or in charge, or something cuz they see the other nurses asking me to help them start IVs and such.  NOT!  I am low man on the totem pole, temporary!  So, what can i do to chill out?  Ack!  Not an option........rant over.