Desktop Files Missing

I turned on my MAC computer this morning and realized that all my files that were on my desktop are gone. I restarted my computer and they did not reappear. I also attempted to completely shut down my computer and turn it back on, but the files are still missing. I shut down my computer properly and there is no other reason I can think of that would explain why my files are gone. I had important items in those files. Has anyone else had this issue? Please help!