I understood your concern  and noted the problem as well .I need to ask few more details to make a diagnosis and start treatment and advice which suits you. Pl consult me on Practo , so that I can help you better.book a time slot as per your convenience for consultation.

Kindly discuss for your concern

I don't know how many Doctors on this forum would have had the privilege of having treated a trained and  established singer like you as his patient. Please consult with a Speech Therapist. They may help you.

Can help you with the next course of action and treatment plan. Would like to discuss in details and provide apt solution. Kindly consult.

Can help you, kindly provide detailed history for proper diagnosis and further management

On the basis of your sign and symptom you have some anxiety problem and some tremor in the vocal card during singing . Now according to treatment point of view Inderal 10 mg have propranolol salt that's beta blocker which is give in anxiety , arrhythmia , increase heart rate, and tremor etc. Zepiz-have Clonazepam salt -it's type of tranquillizer of benzodizipine act as anticonvulsant drug - to treat restless and anxiety and abnormal muscle movement and seizure etc. Take these medicines for short periods . Don't take for long term treatment.