Parrot pregnant too long

My 36-yr. old umbrella cockatoo appears to be carrying an egg, but she had had it for 4 months now. In the past, she has laid 1 or 2 unfertilized eggs each year, but has not laid one in about 2 years. She has had "false pregnancies" several times over the last few years, where she appears to have an egg, nests, and adopts a toy as an egg, but the swelling has always disappeared in a timely fashion before.

In addition, her droppings appear larger and a lot more runny than normal the majority of the time, since she has started this latest "false pregnancy. Could it be a bacterial infection?

Thank you!