The picture is difficult to see.
She could be eggnant and getting ready to lay OR she may be egg-bound.
Can you post a better picture?
I would recommend you get her in to see an Avian Vet to ensure she is OK
Avian Vets have special training to determine the cause of symptoms resulting from illness or trauma.
When you rely on anyone who has not had training in Avian diagnosis and care, you may be delaying effective treatment. This can prolong suffering that may be avoidable.
The bird will often require a more intense, prolonged treatment with a poorer chance of full recover than it would have if you seek prompt professional diagnosis and treatment at the first sign of illness.
Having your new budgie examined by an Avian Vet allows you to develop a good relationship with the vet in case your bird needs care for an injury or illness in the future. Additionally, it is always helpful for the vet to have a baseline for your bird to refer to should it need future treatment.