1. Abdominal pains with burning and tightness, aft food, is known as ACIDITY/GASTRITIS/ACID-PEPTIC DISEASE.Causes are multiple. It requires medication , dietary and lifestyle changes.
2.Joint pain with rash
can be an immunological disorder, it has to be confirmed by tests and physical exam.
3. Be prompt and regular with your treatment, lifestyle and diet.
4.You could try homeopathy