Health care professionals are trained to take care of you. No one there is going to reuse a needle to put your health at risk.
We will not participate in your anxiety driven questions to fuel it further for you. Your thought thats starts with "What if" is the crux of the problem.
If you saw her reusing the needle we have a conversation or this is leading us nowhere.
This is the best this forum can offer you, you need to see a therapist for your irrational fears. You don't have an HIV concern.
This is an irrational thinking. Please describe your own risk situation, instead of asking hypothetical questions.