Hired for part-time but being made to work full-time

During my interview I specifically said I didn't want to work full-time hours and I was told I was being hired to work 2 days a week (12 hr shifts). (I'm considered flex-time so they are allowed to flex me up.) The manager said I could work more hours than the 24/wk if I wanted but I didn't have to. Well since then we've had several nurses leave causing us to be short-handed and me having to work more. My problem is this floor is known as the hardest floor in the hospital with the biggest turn-over rate. I'm getting burned out already after only 4 months because it's a VERY stressful place. One of the reasons i took the job was because i figured i could handle it if i were only there two days a week! I'm also not able to keep up well with things at home because I'm so physically tired from being gone 14 hrs a day and on my feet non-stop that I have to have a recovery day. Also, my parents are having health problems and are needing a lot of help lately so between them and my three kid's and their activities I'm behind on my cleaning, laundry, organization, etc. My house is starting to look like an episode of hoarders! I'm very over-whelmed right now to the point of feeling anxious all the time. My husband and kids do help but there's just so much to do and so little time. Who should I talk to? The manager was hired for another position so she's leaving. The person who makes the schedule knows I don't want full-time but she is pressured to use me full-time. The supervisors don't care. Should I talk to someone in Human Resources? Ask to go per diem? Find another job? Has anyone ever dealt with this situation and could offer advice? Thank you!
Per diem is a good idea. Turn it around on them; let them know you will be giving them the dates you are available to be scheduled, they are not to be scheduling you without your consent. Then give them the two days a week you want to work. If they are as desperate as you say, they will snap them up without argument.

Thank you for the advice! Who should I talk to? I'm not even sure we have a manager at the moment.

I had a part time job that kept scheduling me for times I was scheduled at my ft job. I talked to the scheduling manager and her response was "I have to staff my department." I pointed out that if I couldn't work when she scheduled me and couldn't find people to switch with and therefore had to call out, she was actually scheduling holes in to the schedule. She didn't care. I went in to quit and the director asked me to stay on per diem, and I did and now have complete control over my schedule. No issues, ever, minimal requirement of shifts to take but I can work as much as I like because they are always short.Talk to whoever you'd give notice that you're quitting to. Be prepared for them to say no deal to going per diem. But I'm a huge fan of the amount of control per diem employment gives you over your schedule as long as you can weather out the lean, low census, well-staffed times.

Quote from hiddencatRNI had a part time job that kept scheduling me for times I was scheduled at my ft job. I talked to the scheduling manager and her response was "I have to staff my department." I pointed out that if I couldn't work when she scheduled me and couldn't find people to switch with and therefore had to call out, she was actually scheduling holes in to the schedule. She didn't care. I went in to quit and the director asked me to stay on per diem, and I did and now have complete control over my schedule. No issues, ever, minimal requirement of shifts to take but I can work as much as I like because they are always short.Talk to whoever you'd give notice that you're quitting to. Be prepared for them to say no deal to going per diem. But I'm a huge fan of the amount of control per diem employment gives you over your schedule as long as you can weather out the lean, low census, well-staffed times.