I am in the exact same position you're in. I'm 23 and going into my 6th year of college with nothing to show of it. I switched my major to nursing a year ago, finished my pre-req's, and applied to schools. If you have all of your pre-req's done, then don't bother taking other classes that aren't going to help you in the long run. You'll end up racking more credit hours, and in my state at least, that is a no-no. I applied to a nursing school for the Fall 2016 semester in June and got rejected. It sucked because it pushed me back another semester, and like you, I hate that I've wasted so much time and money. However, I took a summer class that I needed and now I'm applying again for the Spring 2017 semester and all signs are looking good right now. I know how it feels to be wasting all this time and money with nothing to show but if you're determined to get into nursing school then apply to as many programs as possible and if you there are any classes you absolutely have to take then do it. If you get rejected figure out why and re-take a class or two if that's the issue, if not all you can do is try again.