Crying Baby

My baby turns 8 months tomorrow.. I was always able to put her down awake and she falls asleep on her own. Now it’s non stop crying at bed time. I don’t think anymore teeth are popping through right now and nothing else is wrong. Could this be a Sleep regression??? Separation anxiety?? She still sleeps all night and is good for her naps. It’s only bed time. Has this happened to anyone else?