She fired me on grounds that I had been spoken to about my tone used but in return her tone and threats were also not professional.
I am not admitted to practice law in the state of Maryland, so my comments are general. Unless you can connect your termination to a factor such as violation of public policy, whistleblowing, discrimination based on a protected characteristic such as age, gender, disability, race, etc., none of which you have disclosed in your question, there is likely nothing you can do about being terminated. If you have more facts that you have not disclosed that do connect your termination to any of the issues I have mentioned, you should post them. Further, if your termination is in connection with a medical leave of absence you may be protected.