i would say, no.
did you smell it (the chicken) before, or did you just notice it yesterday (most don't sniff their chickens everyday, but some may)? it may have laid in some poo and had some on its feathers, or it may have just had one of those dark, greasy poo's.
anyway, the ingredients for making the eggs are always there. just like a human, a chick is born possessing all eggs it will ever produce, just at different stages of development. they don't just start accumulating the ingredients to make eggs, one day.
to me, anyway, eggs don't smell like anything, that i would even notice if one was sitting under my nose (fresh ones, anyway, and these would be the freshest of fresh)
i could be wrong, but my answer is "no"
my guess would be that she got into something
edited to say: i guess it is possible, however, that her hormones have started flowing. while i still don't believe it is eggs you are smelling, i would concede that you are smelling secretions due to her body preparing to lay eggs, or even like how a boar starts smelling of musk when it's testosterone is rising