New RN, just had 1st job interviews with HR and Unit Manager, need your advice

Hello everyone, I badly need your advice.

Here is the scenario:

I applied online for M/S day shift - was told in email it was offered to another candidate. I browsed on their website other possible fit for a new RN like me without prior work experience and ended up applying for M/S/Tele night shift, Rehab, and Float pool. Got an interview with HR, where I said (for the q: how do you see yourself in 5 years?) that I would like to either be a CNM or FNP, and that I only liked to start in M/S (when asked which position I was pulled more into) because I believed it would prepare me better for any other specialty I might consider later on. Okay, fast forward, I got into second interview, with the nursing unit manager, and it went well. I was told they would call me for the next meeting, which I am anticipating to be a job offer, although I would not want to hope/expect too much (because I have read of a post about having very good interview then no more follow up). That 2nd interview was last Wednesday, and I was warned by some friends that HR usually plays it cool for a week, but I did not want to sit here being too comfortable expecting a job offer soon when there might be none, so I browsed again for other job ads and applied online last Friday at a nearby hospital.

This second hospital had ads for OB-Gyn night shift (my first priority, given the chance to start there without experience) and Med/Surg day shift. I got a call this afternoon to set up an interview.

Today also, I saw an ad for OB-Gyn day shift in the first hospital I applied to for M/S night. Now I want to submit application also for that position (I really liked the people there and the interviewers), BUT my first two interviews were over, and I am wondering whether I should call the HR to ask her if it was fine for me to apply for that position despite what I told her in the interview that I wanted exposure in M/S to develop competence. Should I ask her opinion on whether I, a new RN, should start in M/S before considering specialty areas or could I start right away in OB-Gyn (she knew I was planning towards that direction when I expressed interest in becoming a CNM). Should I wait until I get that call for the 3rd interview before I ask about the OB-Gyn position? (HR and unit manager both offered their numbers in case I have more questions to ask.)

What do you suggest I do? I do not want to be seen as fickle-minded, but since many have started in specialty areas and had no problems gaining competence in their desired field, I am now also considering NOT spending my first year as a nurse in M/S (which I know I do not like). I like that first hospital not only because the working environment seemed very good, but it has a very good reputation (JCAHO certified and one of last years Best Places to Work in my state). I have yet to set an appointment with the second hospital so I do not have an idea yet of how the people there are.

Your input will be highly appreciated.