Could I still be pregnant

My husband an I have just start trying to conceive, we've never tried this so everything is brand new. My 3 year old was a surprise, but we started on the 24th and ovulation day was the 1st of March. I dont get my period till the 15th of this month so still haven't missed. I am such an impatient person I've taken two tests already thenlast one I took was 8 days before my missed period both came back negative could I still be pregnant ?? I found out when I was pregnant with my son before I missed my first period