Hi thanks for contacting health care magic... Your heart burn and chest pain could be by gastritis associated acid reflux disease. There could be possibilities of viral flu also leading neck stiff.. Heart burn is reffered pain.... Take pentoprazole for two week... Avoid excess spicy foods ... Avoid smoking , alcohol like gastric irritants.... Drink lots of water.... Excess heavy meal restricted. Fruits taken more.... Cooked oatmeal good for stomach soothing. If you develop fever with increasing headache along with stiff neck meningitis should be ruled out. Take care. Consult physician for your condition.