so, I downloaded the new El Capitan for mac and it wasn't working with my university so I followed the directions to hit Command+R and erase it to get Yosemite back, and now I've lost everything on my computer. is there anyway to get my stuff back? like can I take it somewhere (there's not a mac store within 5 hours of where I live). would best buy be able to fix it? I lost 5 years worth of music, photos, papers and assignments I had written. I don't know what to do.