possible false negatives?

I had my last normal period around nov 9th. my bf n i were sexually active until nov 25th ish when we broke up. i was suppose to start my cycle around dec 7th and didnt. around the 11th i had some slight spotting for a few days. i have had mild lower abdominal cramping (not really painful more annoying), a lot of nausea, slightly tender breast to the touch and slightly larger, a little constipation, my lower abdomen is bloated, when i lay on my back my stomach feels a little heavy, sometimes i feel pressure in my lower abdomen, i do have to urinate more than normal, and i have also been having a lot of weird dreams. I have taken like 5 negative test. Could they be false negatives? we didnt use condoms and i did miss a few pills in nov.