What Causes Dizziness And Stomach Pain After My Menstrual Cycle?

Hi,



I am a married lady and have the following symptoms :



1) After my period, I had unprotected sex. Now, I feeling dizzy and have stomach pulse.



2) Occasionally, I feel like vomitting. I did a pregnacy test and it turned out to be negative.



3) My period began on March 7th and end on March 10th. From March 11th onwards, I had unprotected sex almost everyday.



4) I having stomach cramp, in the lower part of my abdomen.



Could it be early signs of pregnacy even when the pregnacy test turned negative ? Please help me....