Please Need HELP Just started new job & found out < $1.50 hour

I'm not sure there's anything you can do. You are not supposed to know the wages of your coworkers for this exact reason. You and the floor workers have different jobs and a different amount of experience. That could explain the difference in wage. As for the other coworker who has the same position, you don't know her employments history or experience level. Just because she is within 90 days of hire, does not mean you have the same employment experience as she does. Lastly, it could just be that the other lady was better at negotiating her wage then you were. To bring it up now would just make you look bad.

It's hard to know what to do 'after the fact'. I would probably leave it alone and ask about a pay raise (without mentioning co-workers' wages) at a job review.

I wish I had thought to ask around in general about wages before I got hired at my first job (which was only 6 weeks ago). I had no idea what to ask for when they wanted to know, so I was honest and told them I didn't know :). Later a friend of mine that works for a different agency (but has a similar work situation) and I were talking about wages. I told her that I thought my pay was awfully low for what I thought a nurse would make. After I told her my base and comp wages she responded "That's not bad for an LPN." Trouble is, I'm an RN! Oh well, I'm learning a lot, and everyone at this company is very kind and patient while I am learning. So, I plan to stay here without mentioning my wages for at least a year.

I think it's too late to say something, but when it comes time for your review ask for a better raise than they offer. Make sure you have proof to back up all of the wonderful things you have done/changes you have made/ways you have saved them money/etc.