I was on my second day of my period and had sex is there more than a 50% chance or lower or higher that I could be pregnant ?

I can happen... and it has happened.

Nobody can venture a guess without knowing EXACTLY your ovulation times... and it might surprise you, its not always rigidly tied to your menstrual cycle... or the same for every woman.

And of course... percentages really are deceptive... just ask someone who was in the 1% of something that never happens 99% of the time.

Unless you are tracking your ovulation, there is no way anyone could tell you.

I don't know percentages or your body's cycle compared to mine but it is very possible to get pregnant when you are on your period. It isn't as likely (or I don't think so) but it can happen. Take a pregnancy test so you can know for sure.