Yes, this discomfort may be felt after a liver-flush for a few days for a number of reasons, including:

Stress on the liver because it is depleted of bile.
Movement of bile, sludge through the bile ducts.
Even stomach pain can be felt in this area as a consequence of waiting for bile which has been depleted.

It demonstrates that you have had a good liver-flush and it will pass. Keep an eye on your stool colour which may be clay like with the discomfort showing that biliary gunge is passing out of the bile ducts. It will gradually turn light brown and then darker to a normal colour over the forthcoming days.