Slight bleeding appx 5 dpo

So my fiancé and I got sneaky and had a quickie downstairs while my son was playing a game upstairs. Nothing rough or too exciting. When we were done, I went to the bathroom to clean up and when I did, I was bleeding. Nothing major- light pink and mixed with other fluids lol. I'm pretty sure it's implantation bleeding. Way too early for a period and I had IB with my son. What do you ladies think? How soon can I test? I have a ladies "booze weekend" coming up and I need to know if I'm pregnant.