You do not count from the LAST day of the period, you count from the FIRST DAY.. =)
It sounds as if you had sex much later in your cycle, and if you are regular, you may not have been at a high risk point.PRECUM CAN get a woman pregnant, especially since you had a long exposure to sex.
I Cannot guarantee anything 100%
You should consider
birth control of some sort, you do NOT need parental consent, and planned parenthood can get you your pills for low cost or even free =)
Did you find this post useful?

2

3