I lost my most important playlist from my iPhone after syncing to my computer today.

I did a sync today from my iPhone to iTunes on my MacBook Pro. I haven't done this in a long time but found some old cds that i added to my computer and wanted them on my phone. After the sync I lost my most important playlist from my iPhone and gained a few I didn't know I had on my computer. The name of the playlist shows up on my computer but only has 8 songs out of almost 100. The playlist is still on my phone but is now empty. Any help would be much appreciated.

I backup to the cloud but when I looked into it it doesn't look like it backs up my music.