which ring finger?

Ma
So, this girl got a promise ring for Valentine's Day 😊 honestly didn't expect it. My boyfriend took me by surprise!
Anyway, I was just wondering which finger the ring should be worn on?  I've googled online that it should be worn on the left if not married, and right if married but different websites say different things. 
This is the ring 😊 not wearing it yet.Â