I Lost My Virginity Unprotected, I Have Taken Two Tests

I lost my virginity unprotected, I have taken two tests at the same time and both came back negative, but I'm 7 days late and still haven't started my period. My symptoms are lower stomach pains, needing to pee often, more tired than usual, lack of appetite, sore breasts, feeling sick in the back of my throat, slightly gassier than usual and feeling slightly breathless. Could I still be pregnant?