Should I apply for another job so soon?

I've been a nurse for a little over 2 years now. My first job was working nights on a med/surg/ortho floor. I worked there 2 years before accepting a day shift position at another hospital recently. I've been at my new job for about 6 weeks now and unfortunately, I'm realizing that taking this job may have been a mistake. The work environment is not very welcoming and my manager is downright hateful (definitely not how she portrayed herself in the interview). There is a position at my old hospital that I would love to apply for, but I'm unsure of what I should do or how I should go about it. I don't want to burn bridges and I've never been one to job hop but, I'm very unhappy on my current job. Should I apply for another position and if I do, should I include my current job on my resume even though I've only been here a short time? Any advice would be great. Thanks.
Moved to Nursing Career Advice for more response.
Yes you should apply and yes, you should include your current job. Just be prepared to offer a reason why you are leaving so quickly. It needs to not bash your current employer. Good luck!
You are in your probationary period, they could ask you to leave at any time, and you can leave at any time, go ahead and apply and follow the other people's advice
That's the purpose of probationary periods....you and the employer will discover if you are the right fit. No harm in leaving for another job. You can be honest and say that you felt x job is more suitable for you, it fits with your interests. There's no employer loyalty anymore, so I wouldn't be concerned with leaving.
Thanks for the responses. I ended up applying for another job, especially after my manager told me the other day that she's moving me to another floor that she's over. 5 weeks of orientation on one floor only to be moved somewhere totally different. There are several things that have gone on that I don't feel comfortable with so hopefully I can find a new job soon.