Where you taking a 21 or 28 day pack?
Birth control pills are 99% effective.
That said it is ok that you missed the last pill since it was a sugar pill.
That would not change your protection.
Of coarse abstinence is the only 100% guarantee.
There is a 1% chance that when the pill is taken correctly that preganancy can occur but the pill you missed do not increase those odds at all.
Thanks for clearing that up.
Unfortunately you might not like my new answer.
There is a chance you could have gotten pregnant but ovulation usually takes place around day 10-14 so it is a good chance that you missed your fertile time.
You might even miss your period because you missed a pill so don't automatically freak out.
Just take a test.
Here is a great chart that can help too.
Your chances are good with taking the active pill.
Wait a couple of days if you miss your period and then test.
You might possibly have to take a couple of test since your period could be thrown off now.
That is important news that you just had your period.
I think you are not pregnant.
The chances of getting pregnant will on your period is almost nonexistant.
Plus the fact that you took the extra pill I think you are safe.
Your chance of being pregnant is the same as if you hadn't missed a pill since sex was when you were on your period and you took the extra pill.
You can relax.