Late period? Implantation? Spotting? What?

Hannah

My last period was June 27. according to this app, my period was supposed to start Aug 5th. Well it's been a week and nothing. Me and my husband "kinda" had "sex" (turkey baster, long story) 3 weeks ago.

when I wipe there is some light brownish color. Could it be implantation or spotting or am I seriously about to start my period while I'm at the beach on vacation today and tomorrow?!