According to the Massachusetts Wage Act, G.L. ch. 149, sec. 148, your paycheck is generally owed the day of discharge. I would suggest you consult counsel and file a complaint with the Attorney General's office.
Under the Wage Act, the empployer must pay on the day of discharge. Required payment includes any money owed for earned paid vacation. I would demand payment and, if that does not work, contact counsel. In order to proceed under the Wage Act, you must first file a complaint with the Attorney General's Office. Counsel can do this for you.
I agree with the previous posts that Massachusetts law requires that you be given your final paycheck on the date you are discharged. However, if you are paid in full a couple of days later, from a practical point of view your damages will be very limited.