I had her blood work done this morning and she tested negative for heart worms. Yupppeeeeee!!!!!!! I'm going to have her tested again next year just to be sure. Itzel's vet is going to order the medication for me and it should arrive within 2 days. He's ordering enough for a year, so she'll be okay until next year. I spoke to him about the Drs. Foster and Smith site and he said it was a good option if the medication was really pricey over here. But it's at a great price over here and available, so he went ahead and ordered it for me.
Thank you everyone again for the help.