I had sex and the next day a rash (round) appeared all over my hands, no fever, diarrhea or other symptoms. Before I knew it I had a rash on both sides of my torso, my back, my legs, and my face. That night my lip and tongue were swollen so bad that I went to the emergency room. Now 4 days later the rash is gone and so is the swelling. My boyfriend took an hiv test rapid (elisa) and it came back negative. He is the only one I have been with. He said that he was with a girl about 6 weeks prior. He does not show any symptoms or rashes. Could acute infection show up in less than 12hrs? Is it possible that I was infected with a virus?