no period, neg test, with symptoms

My husband and I are trying for number two. I got off birth control in April. May period normal, June 6 period a few days late but normal. July no period. Took preg test July 12(one week late) – it seemed confused neither positive nor strong negative. Took test week later, same thing, not positive but very weak negative. Tried a different brand a week after that. Test neg. I have been irritable, no tenderness(didn’t with my first) Having mild cramping and weird pregnant like discomfort. A few weeks ago i was puky feeling but now I am just overly tired. I am waiting for August just to see if I start another period. Can preg test be duds andor be wrong?