Discrimination?

The hospital I have worked at for 6 yrs is being bought by a large health system in town. They are providing offer letters to all staff then requiring a UDS and physical as if we are new employees. The letters went out in stages. In my dept. the last 5 employees (including myself) to receive their letter all have FMLA. I have a chronic illness, also considered a disability, so I have intermittent FMLA to protect my job for those few days I need to call off. I was concerned that I had not received my letter and asked the director and she said she knew "they" were reviewing files of employees with FMLA. My concern is the new powerful health system will find a reason not to keep me on due to my illness/disability. If I were applying for their hospital as an outside candidate, they would not have access to my employee files and would not be allowed to ask me about my medical history. Now, one week later, after only receiving a counseling once in 6 years for being upset about a process change, the same director as above wrote me up for insubordination about a misunderstanding. Even she said she knew I didn't realize how I came across sometimes, but still called it insubordination. I feel I am being targeted now because of my health during the take over. Is there anything I can do?