Could I Be Pregnant Despite A Single Positive Test Followed By Multiple Negatives And Ongoing Symptoms?

I ve been trying for a baby for 3 months now. I had one electronic pregnancy test. Tell me I was pregnant. I have taken lots of pregnancy tests after the first positive and have all negative tests. Recently I ve been getting severe backaches bloating that doesn t go down. Cravings for chocolate headaches feeling dizzy, feeling sick. Tired all the time and just feeling drained. Could I be pregnant