What happened to my cheekbones? What are my options? (Photo)

I’m comparing 3 pictures from last year nd 3 from this year.(1,3,5=last year, 2,4,6=this year)As you can see, my cheekbones have just gone away (haven’t lost weight.) What happened? Is there an explanation for this? Also I want to consider fillers but I am only 18 and I don’t want to have to keep getting fillers for the rest of my life. Are there any other options available? Something more long term maybe 5 year fillers? Help! Thank you!