The purpose of the PB is to keep your bowels moving. Since you stopped because you had constipation, that's a worry.
Are you able to do an enema? You don't want to be constipated when you do a liver flush. You want to give the toxins a clear path out.
You should drink lots of pure water starting right now and clear out with an enema (a few bags) before you flush. The enema can happen tomorrow morning. And you can flush at night.
Apple juice does melt old bile and softens the stones. But you would have had to start sooner (like 4 days ago -- about a quart a day).
Are you going to try Epsom salt? Then you should be OK, because this will move you and open up the bile ducts for easier stone passage.
Eat fat free tomorrow. Read up on the Epsom Salt flushes, though, and decide how you want to do it. I can't offer anything here, since I don't use ES.