Civil collection action, non-appearing defendant
A legal proceeding upon a debt is a civil action, not a criminal action. You are not in any danger of being imprisoned for failing to appear in a civil action. The creditor, Capital One, however, may have taken an order of default against you either at or after the scheduled hearing. From what you write, I understand that you were and are not represented by an attorney. You have several options. First, to learn what occurred, you could call either the court clerk or the creditor, or you could contact an attorney to get this information for you. Second, you could contact a credit-counseling agency, and seek help in putting your financial affairs in order. As part of that process, the credit-counselor would get accurate information about all of your indebtedness.
Linked below is the National Foundation for Consumer Credit website (http://www.nfcc.org/).
Another link is to the Consumer Credit Counseling organization. Both have links to offices in Massachusetts.
You are not in any danger of being imprisoned. Ant to avoid further damage to your credit rating, you may wish to meet with a credit counseling agency.