Following his loss at Hell in a Cell to the returning Alberto Del Rio we didn't see John Cena on Raw last Monday. We also won't see John next week either on Raw or Smackdown. The reason we won't see John is because he actually is taking time off from WWE. After around 2-3 years of consistently being a part of every show and had been very healthy so I don't really think that this time off has anything to do with an injury.
Apparently John is taking time off to film for a new fitness show comparable to the Biggest Loser that will air on Fox starting in 2016. However, this is just a rumor at this time but if it is true then this would John's biggest project outside of the WWE because said show has no ties to the WWE in any way. John has also become an even bigger star because of the meme about him that has been circulating around.
At this point John Cena is set to return before the end of the year and it is rumored that his first feud back will be with Alberto Del Rio over the US title. Right now Cena is set to return around the TLC PPV, but has also been rumored to be missing the TLC PPV. Now we just have sit back and wait and see what happens, because I have heard that were suppose to be getting a changed John Cena back following his hiatus from the company.