Thanks for writing in.
The reason behind it could be either false positive pregnancy test or real pregnancy with low hcg
False positive test could be due to following reasons-
Hcg containing drugs, less urine drops used in test, test read after long time, proteinuria, chemical pregnancy
causing periods to come at regular interval].
Even low hcg levels can cause similar reaction.
I would recommend you- not to worry. Pregnancy is nature gift to women, wait for 2 more days without stress
and take things positively.
I hope this information helps.