If I was nearly 6 weeks pregnant (4 weeks past ovulation) would I definitely be able to tell?

I had a light and unusual period which was a day late, and have had night time nausea. I also have been eating a lot more than usual and just feel off.

I took a pregnancy test last week and it was still negative but is it possible for it to be still wrong?

I want to be pregnant but my AF came and I felt so sad but she was soooo unusual, lasted only 2 1/2 days and started BROWN and then PINK. Then it was heavy for 2 days.

PLEASE TELL ME IF I SOUND PREGNANT