Is the impact of breastfeeding HCG level?

Location: I can nurse my son 10 months old – often at night. Expressed milk (1-2 bottles) during the day and pump only once during this period. Still have not had a period since the birth of my last baby. My husband and I had an incident of unprotected sex, only two weeks from yesterday. I felt some of my relatives pregnancy symptoms, including pain nipples and mild nausea. I tested with the first test (which has generally been positive during my pregnancy other about 2 days before missed period), with negative results. Question: I know it is possible to conceive before having an initial period, especially after 6 months the baby and breastfeeding is not as common. However, the impact is not carrying out breast-feeding in the level of HCG and the first test will cause a false negative, which means I'm pregnant and not a result positive for another week?

Breastfeeding is not the impact of hCG levels. Repeat the test. If you keep testing negative but still feel you are pregnant, consult your doctor for a blood test and an exam.

Deliver Me – Breastfeeding