I took my bird to a private vet clinic today, but they didn't know what to do.
They didn't want to prescribe any medication for my budgie, and they sent me to Veterinary Faculty, where they told me that I can get my budgie checked, and that they will take some samples for microscopic analysis, but I need to wait for 3 weeks for my appointment
I don't have any other choice but to wait, because private vet clinics won't treat my budgie without microscopic analysis.
When I got home, I cleaned cage, and everything inside with hot water and vinegar.
I forgot to mention that I live in Sarajevo - Bosnia and Herzegovina, where we don't have specialized bird vet, we have only common vets that treat all kind of animals.
P.S. Are you sure that my budgie is a female? I was working hard with my budgie for this past year to teach him/her how to speak, but he/she didn't say a word yet
Here are additional pictures of my budgie, for gender determining purposes