I Fell Hard, Directly On My Tailbone About 2 Weeks

I fell hard, directly on my tailbone about 2 weeks ago, It took my breath away. I've had both hips replace and am waiting to have my shoulders replaced. Last hip was in May 2014. It was not getting better so I went to my doctor who sent me to have xrays. The results said I had a fractured Coccyx, but it appeared to be an old break because it was already healing. Is it possible for it to be healing that quickly, yet looked like an older break? I didn't have a chance or ask, how much older? I'm 55 and this is the first time I've ever fallen? Thanks