Confused feel pregnant but tests are saying negative, help

I’ve been feeling sick and have little cramps for 4 weeks now had the flu which I get everytime I fall pregnant, with my last pregnancy it took 5 weeks for it to go positive and I knew I was pregnant the hole time, I just don’t feel right my stomach is swollen and I can feel my muscles moving around just didn’t know if it could be something else or it’s just happening again and it won’t give me a positive till I’m at least 6 -7 weeks would that be normal for it to happen again?