I got a late 1099-I from my bank w/ $65 in interest paid to a savings account. your system shows I owe the IRS $6! Six dollars! Do I need to file an amended return?

You are supposed to file an amended return, because your tax amount has changed.  It is up to you to decide if you will or not.  If you don't, the IRS might adjust your account as a math error or could assess penalties and interest for not correcting it.