from psych to nursing?

I graduated with my BS in psychology two years ago. I worked in the field and hated it. Now i want to go back to school for nursing but am unsure what to do. Is it best to go to a community college and just get a nursing certificate? and if so, what will you be considered? What makes someone an RN? Sorry, I am confused with all of this. Any help would be great on what path i should take from here. i would like to do it the quickest, least expensive way possible.