Daisy, she doesn't SENSE your pregnancy, she can smell it, you emit it from every pore in your body ... I wonder if it has to do with your progesterone levels, which will continue to rise ...
Frankly, I have hardwoods that are 80+ years old and aren't pretty. In a way I wish I HAD concrete so I could put down new flooring ... cheaper, easier and sturdier ... refinishing is just out of the question for us now, at least, if ever.
Long story short, you have a choice, pull up the carpet, clean from the concrete up, replace any padding that might have been involved, and clean the CRAP out of the carpet, top it off with a cat repellant ... or just rip up the carpet and put down a wood floor.
YOU WILL NEVER GET THE ODOR OUT JUST BY SPRAYING IT WITH STUFF (you could do it sufficiently to find the room pleasant again just for a human, but we're talking eliminating the odor from an ANIMAL's PERSPECTIVE, so just get that idea right out of your head

. Just because human noses can't smell it doesn't mean a cat can't. They aren't dogs, but their noses are still infinitely more acute than ours). Anyway, either she's responding to the hormones you're emitting, or someone stepped in cat or dog urine outside (it wouldn't have to be much, just a drop would do it, if it was marking urine) and tracked the odor into your house. No matter what the cause, every time she passes that area NOW it occurs to her to remark the spot, because she's smelling HER marking. You won't be able to get her to stop marking because that's like asking her to stop eating or breathing, it's instinctive. She smells that odor, her instinct is to mark on top of it. You have to make the smell utterly go away, and enzymic cleaners, as good as they are, CAN'T get it out of every fiber of a carpet (maybe if you UTTERLY saturated the spots on the carpet and let it sit, and TOTALLY replace the chunk of padding underneath, then followed up with a healthy dose of NO-GO after the carpet totally dried ???)
Then the question becomes, did it soak to the concrete underneath? No matter how clean you get the carpet, the odor can still come up from beneath, and that's why you've got to get EVERY molecule of it.
Without taking that section of the carpet up, working all the way down from the floor up and UTTERLY eradicating the odor that reminds her to re-mark, you can't win.
Sorry for the novel, I'm just trying to save you headaches ... been there, done that.