Pregnant again??

I’m 8 weeks pp from my baby boy and I’m scared I might be pregnant again. We have been very careful to use condoms and I’ve taken two tests that came back negative. I’m having some cramps, spotting, and food aversions. I also just got over being sick. All of these things happened right before I found out I was pregnant last time. Am I just being super paranoid or should I be concerned?