SPOTTING is NOT a sign of pregnancy.
IT IS a sign that you missed pills, or started a pack late. Spotting usually happens when you do this.
It is not good to keep missing pills during the month, THAT CAN lead to pregnancy by CAUSING BREAKTHROUGH OVULATION.
WHENEVER you start a new late, even if you 'double up' like you did, you need to wait 7 full days before you are FULLY PROTECTED.
By starting this pack late you are at an increased risk of pregnancy..
BUT your spotting NOW is not a sign of pregnancy at all, just a sign that you took the pills later than usual.