Well, normally my BPs poop 2-5 days after being fed. Usually it's around the 3-4 day range, but it can vary sometimes. Sometimes snakes won't even defecate for a few weeks, or maybe a month, or maybe even a day after being fed. It really depends on the snakes because all snakes are different and you will not always expect your snake to defecate a few days after being fed.

As for the shedding, when a snake is going into shed, look for these signs:
-Belly is turning pink
-Scales are rather dull looking
-Eyes becoming a bit cloudy
-Snake is soaking in water dish frequently (though, this doesn't always mean the snake is shedding because there could be a variety of reasons)

Those are the main things you should look for when your snake is going into shed. Sometimes, snakes may become aggressive or a bit nervous when shedding since they can barely see when the eyes are a cloudy/milky blue. That's why it's best to leave your snake alone during shedding, just so you don't get bit if the snake happens to be aggressive during a shed.