Implantation bleed or Period

Hey guys, so according to the app, I was ovulating March 10-16, my period is suppose to come on the 29th. I have unprotected sex all the time( yes, I was having unprotected sex during my ovulation time.) I was spotting March 16 a tiny bit and then it stop. It was a light red or pink and you only saw it when I whipped. March 21, I started again but it was reddish brownish and it has been 2 days. I’ve been feeling nauseous for 3 days. I haven’t vomited but the urge is strong. Can this bleeding be implantation bleeding or period? Should I wait until after a missed period to take a pregnancy test?