Don't panic about the pooping just yet. You really have no way to know if there is anymore in the system ready to go. It may be that he felt ill from the blockage and hasn't eaten as much as usual, and when the blockage was removed all the available poop was also.
So, do keep offering water on your finger, veges etc, as suggested. There is not a lot more you can do, if the blockage was removed in time he should recover. If the blockage was caused by an underlying issue he may not.
Best wishes for you and him. Let us know how he progresses.