I hope this message finds you well, present circumstances excluded. I am a licensed attorney with over a dozen years of experience. It is a pleasure to assist you today.
First off, I am sorry you are having to go through this issue. Second, and to the point of your inquiry, the physician is likely trying to protect herself and you by performing blood work to make sure that you are still okay to receive the specific dosages that you are receiving of medication. It is a malpractice issue for her if you cannot come in to refill the prescriptions. Therefore, she is legally protected.
In the meantime, you should call and see if there are any services that your physician is aware of in the area that will come and perform the necessary blood work on you at your residence and get them to a lab so she can fill the prescription. If they are not aware of any services, then you still need to see if you can locate one on your own. There are services in some locales that will send a nurse to perform the work, take BP, etc.
If that is still not available, your only options are to either arrange a visit, somehow. (that seems to be impossible). The other option is to call an ambulance via 911 since this can be an emergency circumstance for you since you do not have the requisite medication to breath.
I wish there were more legal options here but there are not, I am afraid.
Let me know if you have any other questions or concerns. Please also rate my answer positively (THREE OR MORE STARS) on the ratings bar on your end so I can receive credit for my responses from the site.
Thank you and best wishes!