My Daughter Fell And Hurt Her Tail Bone Area, She

My daughter fell and hurt her tail bone area, she now has pain and swelling accompanied by a popping sound?? She can hardly sit down. We took her to the ER and had ex rays done but nothing , they say it was bruised but then the next day it popped in the shower so loud I could even hear it, '' I was in the bathroom with her '' but still, is this right? she says the pain is just getting worse! I guess I'm gonna take her to the Doc again tomorrow?