R.J.
It's totally normal with a lot of gas.
Reason being... gas creates cramps. The cramps and pain interfere with smooth muscle movement that propels poop down the shoot. So poop backs up in certain areas where the smooth muscle isn't doing it's job, but flows fine in other areas where the smooth muscle is working correctly. As the gas is lessened... so should the back up sort itself out. It nearly always does (hence the waiting a few days).
Another note on gas: Some babies need marathon burping. This means half and hour to an hour of burping after feeding. You'll get some decent burps in the beginning but then somewhere between 30-60 minutes later you'll get a dinosaur burp. Bwaaaarrrrr!! (I expect to see ripples in cups and an approaching Trex). For babies who suck down a lot of air... only some of it goes UP during "normal" burping sessions. The rest continues down into the intestines. Creating sooooo much pain.
My son was a "marathon burper". I read the entire 70 book Nero Wolfe series (quick reads), all of the Jean M Auel books, all of the Stephanie Plum books, and got halfway through the Amelia Peabody mysteries by the time my son didn't need to be burped anymore. (I'd never read mysteries before, but got on a real kick). Just tossed him over my shoulder in the rocking chair, held the book in the same hand as the baby, and patted with my other hand.
It was an accident that I found out he was one of those marathon burpers / sleep burpers. I'd fed him and started reading a book while burping to stay awake. It was at a "good" part, and when this MONSTER burp sounded in my ear (seriously... how DO they get that much air in there?) and I looked at the clock and realized it was an hour later. From then on, as long as I waited for the "round 2" burp... all of his gassiness and colickiness went away completely. But if hubby or nana was watching him... no matter how much I begged they'd only burp for 5-10 minutes tops... it came right back.
Anyhow... just thought I'd share "in case".