My period is about a month late and I have taken multiple pregnancy tests. I have been feel very fatigue and have been having headaches and heartburn. I have also been gaining weight in my stomach area which is not normal for me since all my weigh usually goes to my thighs. Just recently my breasts have been getting sore, also the area around my vagina has been very itchy and sore. What could be causing this?

Tests can be negative even if you are pregnant, so go to a doctor, and also get what is probably a vaginal yeast infection treated. Your pH is probably off (also a sign of pregnancy). Of course it might be something else entirely. Countless women have 'signs' and aren't pregnant at all, just pre-periodic, gassy, have edema for all sorts of reasons, or no reason.