how long does it take to actually lay the egg, anyway

When mine first started laying some did lay in the box longer then others. Heck my cochin hen became broody after laying only a dozen eggs! She is in the nest box constantly now. I wouldn't worry.

 

hens can sit and rustle around and rearrange themselves for hours before every laying their egg. No need to worry. She may not even lay one and is just there for her own reasons. LOL

 

They can sit in the nest boxes for a long time and not lay any eggs. I don't let them sleep in the nests at night. Mine tried and after a few poopy eggs I stopped that.