It could go back to the house, the house could agree with the senate, then on to the governor.
Wait, I was celebrating. Is this not final?
If they pass two different versions of the Bill, then it must go to conference to iron out the differences before it can be sent back to both the House and Senate for approval (a single Bill), then, if passed by both chambers, it is send to the Gov for signing.
Receding to the Senate is done, but must pass conference first.