Legal Question in Civil Rights Law in Maryland

Your question seems to involve 2 different areas of law:

First, the shift breaks. In certain situations your employer MUST provide breaks, though whether or not this applies to you will depend on the size of the employer, the # of retail employees and the nature of your position. Commissioned and executive employees are usually exempt from the requirements.

Second, employee discipline -- generally speaking if you are not a contract employee (few employees are) the employer may discipline or even fire for a wide variety of reasons (whether or not they are reasonable) so long as they do not illegally discriminate.

You may want to consult with an attorney to talk about your situation in greater depth. Please note that this online post does not substitute for specific legal advice and the details of your situation may affect how the law applies to you.