If it's really that bad, try transferring within the facility. Go to your manager and tell him/her that med-surg just doesn't seem to be a good fit for you; could you in-house transfer to another floor. More than likely there are openings on nearly every floor. If you can, visit some of the other floors before you talk to your manager so you can get an idea of where you'd like to go. Don't whine about how you are being treated unfairly, so-and-so said this to me and chewed me out for this mistake, etc. You don't want to get yourself labeled as "someone who can't get along with her co-workers."
Some of the nurses where I work have made it their goal in life to make the new nurses feel bad, and there will always be competition between the shifts. If a mistake is made, and the person who made it is not on the same shift as you, for some reason, it just makes it SO much worse. It IS a pain in the @$$ to have to either work around or fix someone else's mistake. If your co-workers (either on your shift or on the next) fix all your mistakes, you'll never learn from them. I had a patient a couple of weeks ago who went for a heart cath on the weekend. Cath lab didn't fill out the pre-op form, so the nurses I was working with said not to worry about filling out the post-op form, just make sure I address everything in my nurses notes (which I always do anyway). Well, I came back to work Tuesday night and the post-op form was hanging on my locker, with a big note from one of those busybodies that like to make newbies feel bad, saying, "THIS FORM MUST BE FILLED OUT FOR ANY PATIENT RETURNING FROM SURGERY OR CATH LAB." Then one of my co-workers told me it had been hanging there since Monday, for all the world to see. The patient wasn't even in ICU anymore. So I filled out what I could remember (without the chart), wrote "see nurses notes" for what I couldn't, and send it to the floor where the patient was to be put on the chart. Now, I could have gone to my manager and said that this woman was picking on me, that so-and-so said I didn't have to fill out the paper because cath lab didn't fill out their part, etc, or I could do what I did, which was not take it personally and learn from my mistake. Of course, that is not the first mistake I made, it's just the most recent that is just so durn nit-picky that I'm still annoyed by it!
As for getting your schedule changed...yes, it does suck, but you are the new person. If they are going to change someone's self-schedule, it's going to be you. Think about it, if you had been working there for 10 years and turned in your schedule, and the new girl also turned in hers, and they couldn't accomodate both of you, would you really be happy if they gave her what she wanted and changed yours? I don't think so. Seniority does have it's privileges. Right now I'm new, work nights (which I love) but sometimes have to float to days (which I don't really like) but I do it without complaining (too much) because I know it's part of paying your dues.