Is this normal?

My last period started on July 22. My cycles are about 43 to 45 days long. For the most part. My husband and I had sex iAugust 23. He is a trucker so always on the road. By August 26 I started feeling nauseous. My back was super achy. I was due for my period soon so I left it to that but I never get nauseous around my period. I took a test a couple days after my period was due but negative. But I’ve been nauseous everyday and almost all day.

With my 2 previous pregnancies, I had little to no symptoms. They were smooth as heck. I was very lucky.

I took a pregnancy test today 7 days after my period was due and got a very faint positive.

Is this normal? It’s crazy because I had a feeling I was pregnant days after having sexual because I’m so nauseous alllll the time. Sorry this may be stupid but my 2 previous pregnancies were super chill and I had no morning sickness.