Hallo, I am a collaborative pianist and a yogini, and I would like to commend you for starting your yoga journey. It is not necessarily a religious practice, but one of integrative spirituality based on Ayurvedic medicine, which is far older than Western understandings of medicine and physiology. The key to yoga is to remember it is NOT a competition; listen to your body and respect what it is telling you. If something hurts, stop. A qualified teacher will be more than happy to give you modifications suitable for you. Also, the benefits of yoga are cumulative...you may not be that pretzel-shaped hot shot next to you, but over time, a regular yoga practice will increase flexibility, strength, focus, stamina...all things that we need as we play.
For those who "pooh pooh" yoga, in favor of more Western exercise, let me say this: I have been injured far more frequently as a result of traditional exercise, and more frequently injured from playing with incorrect technique.
Namaste.
Hannah