Pregnant or no?!

Okay so me and my boyfriend had sex pretty  much my entire fertile week/period. It's been 16 days since we last had sex but of course, sperm lives in the body for up to 5 days post. And now I'm experiencing brownish spotting and eve tells me that my period is expected in 1 day. The thing is I've never had spotting before any of my periods (I'm 19), let alone brownish spotting. I did my research and found out implantation bleeding happens up to 12 days after fertilization but about a week before your next period. Yesterday (May 11) is when the light spotting occurred, still in the time window on when I could've been ovulating. Except this is CD31 for me. Should I just wait it out and take a test within the next few days?