Please help feeling extremely scared

I reckon if I sat and took notice of every small pain I felt in my body I would probably be a nervous wreck 😃 I'm wondering if there is something else underlying this, like a mental health based issue? That may explain your loss of appetite. Anxiety is a real appetite killer but I'm not sure whether it's that you don't feel like eating or whether you feel physically like you can't eat because something is getting stuck or it's painful. If it's the former then it sounds like generalised anxiety syndrome and maybe your constant worries about your health are an attempt to control something else in your life?

Might be worth thinking about and asking for some advice on this because it seems like you're on a bit of a loop of being told you don't have a certain condition and then immediately shifting your focus onto another. All scenarios seem catastrophic as well and you don't allow yourself the (more likely) possibility that it's actually something pretty minor. You may want to explore this with an appropriate professional so you can get the peace of mind you clearly deserve.