2-week-old kitten fell down in front of her mother? :(

About two weeks ago, a feral cat gave birth to two kittens in an unused trash chute. 

Since the area had quite the number of cats prowling around, I occasionally feed the momma so she can support her babies. I usually open the trash chute to check if she's inside and deposit the food. Also, I've been observing the kittens and they seem to grow well enough. (one of them has learned to spit at me, haha)

Today, I noticed that the mom cat is outside, and I gave her a piece of boiled egg yolk (is this ok?). Then out of curiosity, I opened the chute to check on the babies, and one of them fell out since they apparently like to sit on the edge. The baby landed on its belly, and it seemed fine. It's still wriggling its paws around like it's trying to crawl. The mother witnessed all of this and repeatedly meowed at me, but she didn't seem agitated...(I hope)  I quickly picked the baby up and put it back into the chute, and shut it. 

The mother stopped eating but after some coaxing, she ate again (though she didn't seem to be a fan of eggs). My question is - will she be alarmed after what happened today? Will she think of me as an enemy and move the babies away? And will the baby be injured? The chute was about 1 or 1.5 feet from the ground - I seriously hope baby kittens are tougher than they look... 

I hope the fall wasnt dangerous, yes, they are more sturdy than one think...

As mom didnt reacted immediately, she will not move because of this.  although feral moms do move now and then, if nothing else, so they dont want their nest to become smelly.  So when the old nest becomes smelly, they moves.

But this is all guesses, we cant know for sure now...

Yes, egg yolk is very nourishing.

Thanks for the reply!! The kitten didn't mew at all when she fell; she just kinda lay there and wriggled around as usual. I picked her up and once she registered she was being lifted, she kinda mewed frantically... I hope this was just a sign of fear and not pain? She moved her paws around normally, so I really think she doesn't have any broken bones...

I'll try to check on her tomorrow. But I'll make sure I have a board to support them just in case the kittens are sitting on the edge again... 

 I think the kitten was probably fine,  it doesn't sound like the mom was too concerned.  so I doubt she would see you as an enemy for this reason.  and if she moves the nest it is probably just because, as Stefan says,  they usually have an instinct to move the nest  to lessen the risk of attracting predators by the smell.