Are period-like cramps normal at 4weeks

Emily • Tue, May 19 • Trying for baby #1 since Feb 2019

I took a pregnancy test yesterday because AF is 2 days late. It was positive, but now I am feeling like AF is still coming. I have lower back aches and mid-lower cramping in my abdomen/uterus. Is this normal?? I only had one spot of blood the day my period was due, nothing since.