Withdrawal bleeding

I went for a blood pregnancy test because I’ve been feeling nauseous, etc and came back negative yesterday. I recently quit birth control and I’m having my withdrawal bleeding. My question is...is this my period? Not to get too detailed but this has blood clots , does a withdraw bleeding have that, too? My fiancé and I do wear protection. Yet, I’m still feeling pregnant like. Will I get another period soon after this one? Thank you.