Ok guys I need some help

I’m 22 and we recently just started trying to have a baby . He came inside me on the 16-17-18 and then on the 20 th I dark red some was brown bleeding but very light then on the 22 it turned baby pink on the liner ? I’m so confused 🤷🏼‍♀️ my period was supposed to be December 8th but nothing I had slight cramping but not like my normal cramps where u feel like u are gunna die . When should I take a test ?