Condom broke.

It is impossible to provide you with your exact chances or risk of pregnancy, as every woman's body is different. However, for most women, most of the time, this would not be the most fertile time in their cycle, and pregnancy chances would be fairly low compared to high chances during your mid-cycle.

For most women, most of the time, their most fertile time is in the middle of their cycle (usually referred to as "Day 14" in a regular 28-day cycle, plus or minus 5 days on either side), as ovulation occurs most of the time mid-cycle, about 2 weeks before your next period.

There are a million different caveats, but if you had sex on/about "day 6", then this would not have been during your most fertile time. Sperm can also live inside a women's body for up to 3 days, and is also a reason that your fertile window is longer than the length of time the ovum is viable---sperm can be "waiting" for the ovum (egg) even before you ovulate (in other words: you may have not had sex during a fertile time, but the sperm could wait inside your body for 3 days until you are fertile).

Be sure to use plenty of lubrication on the condom to prevent condom failure in the future, and you can read: Help! The condom broke during sex. Tips to prevent "wardrobe malfunctions" for further information.