Are Nausea, Insomnia And Sore Chest Signs Of Pregnancy?

Recently I have taken 4 pregnancy tests, 3 negatives and one positive. But the positive came a day or so later. I tested 1-2weeks ago. I ve read about women who have had the same experience but were pregnant. They say if its grey and very very faint, its still negative, but if its got colour to it ( blue/pink) its positive. Its blue line. But if I am pregnant I d be 6 months along. My stomach has been growing like crazy and I keep getting period like cramps, even though lately I ve been eating better and doing a bit more exercise. I am never comfortable for long and feel weird movements in my tummy. I ve been tired for months. Barely sleep, sore chest, shortness of breath, headaches. I feel nauseas 90% of the time. But I still get monthly bleeding. I ve also talked to women who are mums whom have had the same experience