I'm not sure what's going on ..

For the past few days I've been feeling a bit sick. Most of the time it's when I eat or drink anything (besides water) but the last two night and earlier today I felt sick without eating a thing. My stomach felt really right and I felt like I could possibly throw up but I wasn't that close and I haven't thrown up at all. Also my lungs have hurt but only one time. 
There has been ppl around me getting sick but I don't think I got it cuz they all had it for only one day and then it was gone. 
What is going on?