Hi Aspen Chloe

I honestly have NO idea what it was! She wasn´t hungry and like you, re-tucked in + paci would send her right back off to sleep.
It had been going on for about 2 weeks. My LO is 17 weeks now and like yours, slept through from week 8.
I blamed it on hot weather, bad day naps now and then, her first cold, etc you name it.
In the end, i have to believe it´s a developmental thing and they just pass the phase.
Good luck!