I was moving music files from my Galaxy S4 to my SD card now half my music is gone why?

[Whyissubmittingthissohard]

Like I said, when I was transferring my music from my phone to my SD card I went back to look at them and some of my music was still in my music foulder in device storage. Meanwhile there were only a few in my music foulder on the SD card. I checked in the other folders on my SD card and phone but couldn't find them. I even tried searching specific song titles but never found them. I figured they might have been deleted but I cannot use the data retrieval because I don't have a computer to connect to. Is there any way I can get those back or even find out what happened to them?