In Maryland, there is no "right" to severance pay. That said, you may want to check your employee handbook, for any promise to pay a severance. If they promised to pay it, and all of the conditions to that promise have been satisfied, then they cannot walk away from that deal.
They also cannot administer some sort of de facto severance policy in a discriminatory manner.
Finally, depending on the nature of your employment duties, you may be entitled to unpaid overtime and/or commissions and bonuses, and not even know that you are entitled to that pay. Even if they refuse to grant you a severance, it may be possible to confront them over the unpaid wages that are owed to you, and settle your accounts with them that way.
Please feel free to contact me for a gratis consult on whether you are owed any additional pay, including overtime pay.
Howard B. Hoffman, Esq.