Ay, common yan sa newborns, mama! Marami sa amin ang may babies na ganyan ang ingay ng breathing, parang may congestion or pusa talaga, minsan it's just because ang airways nila ay still adjusting and madami pang mucus pa. But since baby mo is only 4 weeks old, I'd really suggest checking with your pedia just to be sure, kasi gusto nating ma-rule out kung may nakablock or kung normal lang talaga, especially if may feeding problems or parang hirap huminga talaga siya, better safe than sorry, diba?