pregnancy symptoms but negative tests?

so I've been having symptoms like I'm pregnant like mild stomach cramps, feeling tired overly hungry feeling sick, sore boops. I've taken two tests both are negative. I just don't know what else could cause these symptoms. I'm on the pill so it's not pms. could I have symptoms but just be too early to get a positive result? I've just had a baby 8 months ago so remember how it feels just confused by the tests and symptoms.