These are legit, but you have to use them to direct energy. Visualise the related Angel and ask for it’s help, and see healing energy flowing into you as you chant.
You don’t know what’s wrong with you, so your direction will be generalised. Qi will go where it’s needed, so that’s fine.
You must calm yourself and not fear, as the fear itself is going to make it worse. Fear is a very negative energy.
If the doctors couldn’t find anything the best they can do is give you meds for the symptoms, but it should buy you time to learn more and work on it.
When the cause is hard to find, it’s often food allergies and environmental toxins, that can give really weird symptoms that don’t match the doctors playbook. Try an elimination diet (there are books on this) to rule out food as an issue. Never eat soda, seed oils or soy. Make sure you don’t have mold in your house, etc.