We F***** Up 😰😰

Hey y’all I just had my first baby on December 11, 2017 which means I’m exactly 6 weeks postpartum. Well my bleeding had basically gone away a few days (3-4) before I was 4 weeks postpartum so my boyfriend and I decided to have sex twice. In the moment we didn’t have any condoms but he pulled out both times. Now about 2 and 1/2 weeks later I’m feeling so nauseous and very fatigued. I even threw up! We joke that I could be pregnant but even after throwing up I’m still feeling sick. We plan on buying some dollar tree tests today but I wanted to know if they’d even be accurate? Obviously I can’t calculate if I’ve missed my period because it never even came back so I’m not sure the test will be accurate. Someone please help 😰😰