Does it feel water balloon like? Do you know when she last laid, or if she ever has?
She's young for a reproductive problem, but it can happen. If it feels like fluid then likely ascites/waterbelly, that is fluid leaking from the liver, could be a cancer, infection, organ failure. If it's firmer, then could be infectious material, if she's never laid then she may be an internal layer. Usually the prognosis is poor once their abdomens are bloated, and the definite answer to what's going on may not be known until necropsy, the symptoms can be very similar between the various causes. If vet care is an option then internal laying or some cancers may show up on imaging, but many don't have access to a vet that will do the tests or can't spend that kind of $$. The penguin stance can sometimes mean egg binding, but they usually cannot pass droppings if it's that, and they also can take that stance with reproductive problems, they feel like they need to lay, but cannot, it's just whatever is going on in the abdomen.