Can i get pregnant if i just have sex on my ovulation day and the day after?

Yes: Those are your most fertile times.

NO,around ovulation: The days around your ovulation, so to be safe a week before and after your ovulation day puts you at risk of pregnancy. Of course the closer you have unprotected sex to the day of your actual ovulation, the more likely to get pregnant as sperm can live 3-4 days in the proper environment such as the warmth of the vagina.