Puppy naps – long naps out of nowhere?

I have a 4 month old Portuguese water dog puppy. She’s an angel besides the biting. Typically she’s been taking about 1.5-2hr naps every 2 hours or so throughout the day. This week she started sleeping sometimes 4 hours at one go. Is this a miracle and we officially hit a new sleep schedule or is she sick? Behavior is totally normal during the day and she did just get her last shots about 10 days ago so we’ve been going on walks around the neighborhood but no large exposures that she didn’t have before. She’s also teething. Just feeling anxious and need some reassurance 😅