I would say if your cycles are longer that 28 days (which normal women have average of 31 day cycles) , yes that is when you got pregnant.
If you have a :
28 day cycle : ovulation occured approx. The 7th
29 day cycle : ovulation occured approx. The 8th
30 day cycle : ovulation occured approx. The 9th
31 day cycle : ovulation occured approx. The 10th
32 day cycle : ovulation occured approx. The 11th
and so on....
Ashlee