He said to BBC Sport: "Newcastle boss Rafael Benitez is still trying to bring players in - but might have to face up to the fact that this is going to be a frustrating month for him and just get on with things".
If he can improve a lot during these months - and I am sure he will continue improving - then you never know.
Benitez admitted he will not allow anyone to leave St James' Park, unless they have a replacement ready to sign.
Speaking ahead of Saturday's visit of bottom-of-the-table Swansea, Benitez remained typically coy when asked about Newcastle's chances of strengthening their squad before the end of January's transfer deadline.
"As soon as I found out Newcastle were interested, there was only one place to go, but obviously I don't want to see them go down, because I want to play against them and I have mates in their team", said Shelvey, signed in January 2016 for £12million.
"But the others? We can not sell them because the others are already playing". So we can not say we will let players leave on loan if we don't have a replacement. We have had some people asking but nothing serious and no offers on any of our players. But if they talk about loans we are not interested because we need them.
"We have until the 31st of January and I am confident that we will do what we have to do", he said.
Looking ahead to this weekend's crucial fixture against Swansea, Benitez says he is not expecting an easy game. That might well limit Benitez's ability to make signings of his own this month, but the Magpies manager appears to have concluded that the risk of losing someone without being able to adequately replace them is too great. It is very hard to create chances against them.
"I know Mike doesn't go to many games these days but he must know the squad is in desperate need of improvement".