Overflowing toilet...but weird

[Samantha Klein]

Hey BPers, 

I'm looking for some insight. I have a tenant who called me to tell me that there toilet was overflowing but they turned the water supply to the toilet off. I drive over there and the tenant says "Something weird happened, it was at the toilet rim, I went to use the bathroom faucet and when I turned the water on, the water in the toilet tank started to drain to normal level" so after he said that, I flushed it again and it was acting completely normal now, any ideas? The tenant also said they smelled sewage when it was acting up, and I noticed the bottom of the toilet was wet, and the toilet is loose so obviously it needs to be bolted down more, should I replace the wax ring?