Well, if you notice your cats belly has gotten smaller then it was the day before that could be a sign that she had her kittens, or if you haven't seen her for a while then that could mean that she be somewhere where no one could bother her to have the kittens. Don't worry just wait for her to come back and if you have the time and are able to, follow her and she might lead you to her kittens, just don't pick them up because she could reject them because your smell is now on them. Wait a week or two then you'll be able to hold them. If this doesn't help then I'm sorry but this is all I've got, good luck!:]
