Hi. Me And My Boyfriend Are Panicking Right Now. He

Hi. Me and my boyfriend are panicking right now. He put his finger to me after he ejaculated 3 weeks ago. And I was supposed to have my period this week, I've got my period but it's lighter than usual. I'm really confused if it's my period or it's spotting? I'm still a virgin 'tho. Please, I desperately need an answer coming from an expert.