How popular is this name really?

Kat
My husband and I have been set on Luna Belle since before we got pregnant. 
I am really, really not into naming my kid a hugely popular name though. I was Megan growing up and hated it so much I legally changed my name to something else. 
I personally have met no Lunas in my life and everyone we've told has said they like it and haven't met anyone named that before. 
I feel like I see it literally every day on here though, and I'm worried it's about to explode in popularity or something. I would be crushed to have her be one of four Lunas in all her classes like I was with Megan. 
It might even be too late to change her name tbh. We've announced it and everything. But I'm 26 weeks along now and I honestly would consider changing it last minute if I thought it was really going to blow up. 
What do you ladies think? Is Luna the next Ava/ Mia/ Sophia?