Has this happened to anybody else?

brittany

I’m not sure when I ovulate, me and my fiancé had sex on the 17th of this month and i started bleeding like I had started my period. Later that day it turned into brown spotting very light and went away. Have not started my period back yet. I’ve took a digital pregnancy test the other morning and it was negative. I usually always have a period every month. This has thrown me off. Not sure if what to do. Also me and my fiancé just started trying for a baby. So worried I didn’t ovulate this month.