So I Am About Month Late On My Period, And

So I am about month late on my period, and I was tested 2 weeks ago by blood and peed on 6 pregnancy tests and they were all negative. My last period was July 4th and lasted 5 days, my period is usually normal and I have been off birth control since October 2015. I have been tired and lack of energy, gained weight, always hungry, headaches and some nausea here and there. I also just moved and don't have a new dr.yet. What should I do? Does it seem like a big concern? Thank you