Can this be pregnancy or chemical pregnancy ?

Hello ladies!

So I have irregular period which my period doesn’t come every month my last period was may 20 2024 and then last week on sept 2 ,2024 I started to spotting then my period came for 3 days which was suspicious to me because I normally have 7 days period flow it stop sudden my birthday was September 8 I have unprotected sex that night one Sep 11 , 2024 I start to spot then it turn out to bleeding and a few cloths I was not expecting any pain or cramps not even pregnancy symptoms, I being doing test and see that there is faint line on all 4 of them I do them every morning with my first pee , I’m so curious I went to the doctor they give me exam and my pelvic was close but I was bleeding and I have an ultrasound appointment scheduled for this coming Thursday, I have my son he is 3 years old and I use to have bleeding and spotting with him too , please can any one assist in any information ….