8 days late

Okay so I had a baby 3 months ago and had my first period last month. I am late by 8 days. I didn’t think anything of it because I breastfeed sometimes throughout the day. But today when I was standing I felt super faint as if I was going to pass out!! And been having cramps since ovulation but not period. Could I be pregnant? I would think if I was I would have a positive by now