I Had Unprotected Sex On 1st August, Then I Got

I had unprotected sex on 1st august, then I got my periods on 8th of August. Again on 6th sep I got it. it was as usuall, But on 26th sep I felt a brown discharge and pain in lower abdomen in evening first and then bleeding as normal periods and this again ended with brown discharge on 30th sep. I have read this brown discharge indicates pregnancy. Am I?