General fear, stomach aches, bloating, abnormal heart rate...

Hello
I am a 27 year old male that lately have been experiencing all sorts of sensations in my body; before I start with my symptoms I will mention that I had and probably still have streptococcus, I currently have a 5mm kidney stone and hyperactive bladder - for which I haven't started a treatment yet out of fear of what is happening to me recently.
When I eat, basically it started in my teen years, I don't really chew, I eat extremely fast and I had in the past gastritis and duodenal ulcer, I followed a strict regime and treatment for those. At the age of 18-19 or even 20 I started to get a burning sensation in my back (lungs area, near my spine), it used to come and go as it still does right now, I keep having cramps and some strange pain in my right body part, under my ribs, heart is pumping very fast after I eat and I cannot eat almost anything anymore for 2 weeks, I get scared because of it and start shivering all over violently, I can feel my pulse everywhere too and my heart beats, which are very intense and I lay on the ground because of the fear and I start crying, also I can feel some pulsating pain in my brain sometimes and in the past 5-6 days I can feel some sort of cold stream running through my brain arteries.
The pain that I am experiencing its different from any pain Ive experienced before, I burp without eating or drinking any acidic foods, my stomach seems to be full all the time, even though I don't eat, I throw up, I feel like a knot is stuck in my throat and esophagus, I spit a lot of saliva, when I use the toilet not to urinate, for the other thing, it seems like my intestines are ripped out.
I had a pretty sedentary life for the past 4 years, I use the PC a lot, I weight 53kg - 1.70m height, I don't know if this is related but I am mentioning everything I can.
I am terrified of doctors, needles or endoscopy - basically anything that can go inside of me, that's my other problem, I have a generalized fear of everything that is worsening my stomach problems or it might not even be the stomach.
I can provide more information if anything could review this... I know I suffer from anxiety too, but my stomach problem is terrifying me and my heart too.

Thank you very much!
English is not my main language, I hope I have expressed myself clear enough so you can understand me.