I bought 2 female fancy guppies almost 2 weeks ago, I knew they were pregnant, and I knew that guppy fry is tiny, so I strung a length of dense plastic plant along the top of my tank and I put a sleeve of pantyhose over my filter intake, in case I didn't get her into the breeder box before she had the fry.* 2 days after I brought them home, one of my girlies' gravid spot wasn't black, more of a brownish, almost translucent and she looked smaller, so I figured she had her babies.* I looked around and I didn't see any at all.*
Then she started to swell again, and her gravid spot turned big and black, and today the same thing happened: translucent, smaller, brownish gravid spot, and no fry to be seen.* I'm wondering where the fry is (or if she even had them)?*

* I'm worried that they have been eaten, but I have quite a few plants, along with the dense plants lining the top for them to hide in.* I also know that their gestational period is longer than 2 weeks (or I think a lot of us would be in trouble, lol), which only adds to my confusion as to why, if she did in fact have her fry right after I brought her home, she looks just like she did after having her fry such a short time later.
Does anybody know what may be going on?* I didn't have nearly this much stress with my own two pregnancies, I knew for a fact when they were born and exactly where they were!*

* I'm really hoping that at least
some of her fry survive (if they were born), even if I can't find them, I'm really interested in what the babies will look like when they get older.
Thanks in advance..