A lot of your symptoms match symptoms of a digestive disorder. I would recommend going to a gastroenterologist to just be safe.
There are many things that can be causing your symptoms... it could be gastritis, an ulcer, acid reflux... the list goes on and on but the chances of it being any kind of cancer are actually very very low.
Keep a food dairy, writing down everything you eat and drink, how it makes you feel right away and over time... this will help you see any trends in what you are eating and what might be triggering things.
Try eating some bland and easily digested foods such as mashed potatoes, white rice, tea and try sucking on peppermint candies (peppermint is a natural stomach soother) and avoid any fried foods, fats or dairy products to give your stomach a little rest.
You might find that warm drinks (hot tea) makes you feel better or cold ones (smoothies, 'slurpees', iced tea) because different things work better for different people.
What will help right now is to take a long soothing bath, get in comfy clothes... get something to drink (hot or cold, whatever feels best) and put on a silly movie and curl up to relax a little because no matter what it is worrying will not make it any better and can actually make you feel worse and a little 'sanity break and pampering' can help you better handle what is going on. Am I saying it is anxiety or 'all in your head', nope, not at all... what I am saying is that the best way to care for your body and take control of what is going on is to take care of your whole self.
I have a chronic lifelong gastric condition that is uncurable... and it is the 'sanity pampering' breaks that makes it possible for me to battle it and keep in control of what is going on in my life and my body to my best degree.
I been like this for 12 days I eat get bloated get palpations and when i burp out the gases I am better. But I read the internet and thought since my sonogram came okay I would be fine but now read it can be cancer so scared
reflux won't cause stomach cancer--so don't worry about that one. If you have had reflux for quite a while, it can take 2-3 weeks to heal the damage and inflammation before you start to feel better.