How are your bowel movements? Do you have problem with constipation? Because not having regular BMs can cause some of the symptoms you mentioned. Also you should look after any blood in your stool, mostly black that may indicate a problem in the stomach or small bowel region.
However it sounds like you might have problems with gastric ulcers
caused by Helicobacter
plyori. I suggest you to look this up with your physician who will order a gastroscopy to take a closer look.