not too much to do with them now since they have been painted. I would think that painting countertops would be a last ditch thing to do. Consider, painted countertops in direct contact with food you and your family eat is not a good idea at all. It will solve some of your appearance concerns but could harm your health issues.
I hear that you are on a strict budget and I definately understand that, but I would consider new countertops inlieu of painting.