welcome to HCM! I have read your query and from my clinical experince I can say that -- you have developed infection of respiratory tract and associated gastritis is flared up, causing nausea, vomiting, headache and gastric pain. I can see that you are feeling very weak and unwell, but let me tell you that it is completely manageable, and not serious at all. it s just that you have not taken any treatment till now, that things have aggravated so much. Had I been treating you, I would have given for a course of : antibiotic for infection , may be amoxicillin-Clavulanic combination, along with an antacid, like- rapbeprazole and antiemetic - may be : ondansetron 2-4 mg. One may go for a shot of injectable antibiotic for quick response & later shift to oral medicines. Headache can become better with these, if not, I usually go for diclofenac/ aceclofenac. The above along with: steam inhalation and gargals 4-5 times a day, usually makes almost everyone fit in two -three days. For your chronic gastritis, you should go for almost non-spicy, low oil diet for some weeks. Hope this helps you. Get well soon! Dr. Manisha Gopal