Include some oil in your regime.
One time take 1-2 tbsp of oil with juice.
If no negative reaction, keep increasing from meal to meal, from day to day.
Take a break every few days.
Oil with juice will help cleanse your liver, and by doing that will help rebuilding of your intestinal microbiota.
Instead of taking probiotics, add probiotics to milk and make your own yogurt.
Cheap yogurt makers:
Use home made yogurt with the last enema water, to help re-establish good bacteria in your colon.
Don't waste a good fast for nothing.
Once you decide to end the fast, use that opportunity to find out what foods you are able to tolerate.
Include 1-2 foods at a time in your diet, and watch for reaction.
Learn about Rotation-Elimination Diet