Hi Haroon,
Your thread is very similar to
b737ng-centre-tank-ground-transfer.html
If you departed with one center tank pump inop - the MEL would point you in the right direction. From memory, with one center tank pump inop. you'd have to restrict the payload because the center tank fuel will have to be considered as part of the zero fuel weight in the event of the other pump failing.
There is a remote chance that both center tank pumps will fail so your scenario is not considered. Unless there is a QRH procedure for your scenario, I guess you would be permitted to continue the flight up to a point of landing with enough wing tank fuel available to be legal. The fact that you have exceeded the maximum zero fuel weight would result in a landing inspection - so it may be cheaper to divert early.