My Niece Is 18 Years Old And Started Feeling Crummy

my niece is 18 years old and started feeling crummy about 4 hour ago. Her last recorded temp was 99.8. She is feeling lower rib pain on both sides and in her sternum, it hurts to breath and she's slightly nauseated. I'm a nurse but don't know if it's something more than a flu virus or bacterial infection.