Problems adding individual songs form iTunes to iPhone 6 v 8.4.4

I just updated to 8.44. on my iPhone 6 and am trying to add a few songs to my iPhone. The only options seem to be either syncing my entire library or adding an entire album or genre.

Last time I did a full sync I had double the songs on my phone & iTunes - the sync - in other words, instead of adding only those songs not on the other device it added everything, clogging up my storage. I ended up having to go through and delete about 300 songs from my music list.

HOW DID THIS HAPPEN? I miss the days of my iPod. Life was so easy. It was also easy on my Android. Listening to music is a big part of my day.

iTunes is Apple's big thing...am I missing something???