Friday night I suddenly became nauseous, my temp was 96.6 (my norm is 97.5), I vomited twice over night, was nauseous all day yesterday, and my temperature went as high as 100.3. I also had some low back pain yesterday but I think it was from vomiting, I slept all day yesterday(uncomfortably) and my temp was back down to 96.4 today. What could this have been from?