6wo's cry sounds like she is losing her voice

Looking for wisdom from those who've experienced it.

Yesterday evening, my 6 week old daughter's cry changed and it sounds like she's losing her voice. Quick google search later, I ran the humidifier all night but she still sounds the same this morning. She slept fine and her normal hours, and has fed on her normal schedule without problems, too.

I'll be calling the doctor when they open at 9am, but anyone go through this? What did it end up being? Grateful she's not acting sick but it still breaks my heart to hear.

Thanks in advance, all! 💜