It is too early to say whether you have conceived. The slight spotting could be due to various reasons like ovulation bleeding, cervical and vaginal causes and breakthrough bleeding
that occurs occasionally. You have to wait till you are due for your next period or if you want to confirm whether you are pregnant prior to that, you may get a serum beta-hCG
test done one week before you are due. Consult your doctor for further suggestions. Take care.