Breastfeeding vets! Help!

breastfeeding vets! Is this normal? My son will be 4 weeks old tomorrow and we have been ebf and it’s been going great. I noticed yesterday his lips look kind of white after feedings, kind of like they’re swollen or something. He doesn’t seem to be in pain or anything and it goes away a little while after the feedings, just don’t want to overlook it. The pic doesn’t really do it justice but it’s mostly the inside of his lips. Please advise!