Generally speaking, when a bird plucks out a feather, they may 'tense up' before they pluck it out, then yank it out and make a 'squeak' like noise. It's painful pulling a feather out!
When a bird is molting, the feathers naturally come out on their own with no pain what-so-ever. If a bird is preening and comes across some lose feathers, they may pull these feathers out so as to keep the rest of their feathers neat and tidy.
Birds can have light, medium and heavy molts. A light molt a bird may only lose a few feathers a week, if that. A heavy molt they could lose 10, 20 or so feathers in a day!
As long as you don't see anything that definitely looks like plucking, and there are no patchy areas (i.e. areas that are whiter than normal, or perhaps bald areas where there weren't any before), you shouldn't need to worry!
However, it wouldn't hurt to give your girl some extra bathes during this time!
