Can I get pregnant the day after ovulation once I see the body temp rise?

Yes. In fact, because sperm can live a few days inside your body, you can get pregnant anytime from a few days before to a few days after ovulation. You don't have to wait for exact day of ovulation in order to try to get pregnant. If you're trying to get pregnant, start taking prenatal vitamins to minimize your risk for neural tube defects eg spina bifida. Otherwise, use protection, preferably 2 forms.
Yes . Yes , the egg may survive and be able to be fertilized for up to 3 days after ovulation.