Booting up and and loading issue

I'll start from the beginning. I was simply trying to move an .rtf file to the trash. the moment i clicked on it I got that swirling rainbow icon (this was on the finder desktop). It wouldn't go away so i just shut down the computer, but that's when the trouble started. When I tried turning the computer back on, it seemed fine, but when it got to that grey screen with the apple icon and that swirling loading icon, it was taking way longer than usual, as if it would not finish loading. I turned it off and back on again then actually got through the loading process. But after I tried to log in, nothing happened. it wouldn't load up the desktop, or anything.

Any help would be really appreciated.