Welcome to talk budgies, very sorry to hear of your bird's passing. The only thing we can do as owners is strive to be as informed and knowledgeable about thing's as possible. You did the right thing for your terminally ill little bird, by following the advice of a professional, and releasing her from her pain. I hope you will not continue to feel guilt and torture yourself, you sound as if you have been a good owner, and gone out of your way to provide a happy life for your bird's. We have a lot of great nutritional info here that you can take advantage of, and lot's of other great info on budgies/budgie ownership too.
Sorry again for your little bird's passing...:hug:
Sorry again for your little bird's passing...:hug: