It's your own fault if you didn't outline your terms before you started the work. If you said unlimited revisions or whatever then you have to commit to the clients requests. Personally, I would have done the last revision (didn't seem alot of work) and explained that this would be the last one you would be prepared to do.

Always try and keep clients happy, they will refer you to us and come back for more. Upsetting the wrong people can give yourself a bad reputation.