[souffle]

Hi there - yes she does look to be pregnant I'm afraid.
Pregnancy is only 16 days but she looks to be 12-15 days in those pics.
What type of cage is she in as you need to take out any small bedding areas or tubes as you don't want her giving birth in those. Also the wheel needs removed in case she gets the pups tangled on that.
She must be kept in a quiet place and not handled at all during the first 14 days. She will take care of the pups. If she does have babies then we can guide you on care of mum and babies. Just don't peep or try and poke around near her - only feed and water and leave her be as they can cull the pups.
If she does have babies I would contact the store as they are pretty good at giving extra cages and supplies to support you with rearing. I'd try and rehome them yourselves though rather than giving them back to the store. Good luck and let us know how she does. You usually hear little chirps like baby birds from the nest and the mums normally stay in there all the time for about the first 5 days so that would be a sign she had them.