My favorite BR hasn't laid in 3 days-internal laying?

[the lemon tree]

My most beloved 14 month old Barred Rock hasn't laid an egg for 3 days. This is pretty aberrant for her; she's laid an egg everyday since 20 weeks. I saw her in the nest box this morning for about 1.5 hours yet she didn't produce anything, but it doesn't look like she may be internally laying-she's walking and eating normally, and her tail isn't drooping, which I know are symptoms. What could be wrong?

For the past few days though, we've been having some thunderstorms that may have stressed her out. Other than that, I don't know

.

Any ideas?

 

[OregonChickenGal]

If she isn't egg bound, maybe a little broodiness? Don't really know, just a thought.