The day you conceived is the day sperm met egg, not the day the egg attaches to the uterine side wall. In fact, the moment of conception is the moment sperm meets egg. Sure, that can happen on the day of ovulation -- an egg only has a 24-36 hour window when it *can* get fertilized, after that, it dissolves. So conception either happens the day of ovulation or the next day.
It takes a few days for the egg to attach which would be the day you conceived
Yes you can, it just depends on YOUR body. :)