Can I be harrassed at home while under a doctors care and off work by my employer? Also, can I be terminated by following their instructions on reporting from my personal phone?
I don't think I understand the question "Can I be harrassed." Turn off your phone(s) and don't answer the door (you may consider putting a sign on the front door: DO NOT DISTURB). Nobody can harrass you at home unless you let him.
As for being terminated: Generally, an employer can terminate you for any reason or for no reason at all (similarly, you can QUIT for any reason, or for no reason, and you won't get sued). The exceptions are: the employer runs into trouble if he fires you because of your race, religion, gender, or age. Or, if he has a written employment contract with you (which NEVER happens), he has to honor the written terms. And if he has a WRITTEN handbook that tells his policies, he has to comply with it.