Take to vet just in case if you think this is alarming difference in behavior. Check weight of bird. If weight is below normal, then definitely vet.
If you're not getting to a vet today, wait till tomorrow and check how much is being eaten and if behavior returns to normal.
Also you may want to check out this topic about what happened with my Senegal Parrot. She was making bubbling noises and I was concerned there was something stuck in her throat or that she was sick. I ended up taking her to the vet for no reason. I'm not saying that I know your situation doesn't merit a vet visit but it may give you some insight about behavior issues:
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