Possibility of pregnancy as opposed to gastritis

It seems that the symptoms you described, such as nausea, urges to vomit, feeling stressed out, feeling bloated and having amenorrhea for nearly 3.5 months, could indicate that you might be pregnant. It is not very clear when you did these pregnancy tests (because they should be done after your period is late for at least 5-7 days from the expected date of period onset, but since you report irregular cycles, one can never be sure about that). What you might do at this point is two more of these urine beta-HCG pregnancy tests, taking under consideration that it is always safer to consult with your family doctor or gynecologist for excluding pregnancy as a possibility, by a blood beta-HCG pregnancy test and/or vaginal ultrasound.

Another possibility (if pregnancy is excluded) is that you might be experiencing symptoms of gastritis (inflammation of stomach mucose inner lining). In this case it might be recommendable to visit your family doctor for a blood antibody test (against Helicobacter pylori) or more precise stool H. pylori antigen test, for the most common cause of gastritis nowadays: Helicobacter pylori bacteria in gastric mucosa. Your doctor might also want to do basic blood tests (like CBC, complete blood count, for example), to exclude anemia as another possible cause of gastric inflammation. After finding out the cause, doctor might prescribe appropriate and common treatment for these conditions, like triple therapy or something else. What you might do, to lower the intensity of your symptoms, is to stop taking the enzyme pills, avoid stressful situations, coffee, tea, chilly and spicy food, red meat, avoid foods that cause you extra gasses, like broccoli, cabbage, onions, milk, cooked dried beans and peas, and certain enzyme fruits. Pay attention to the foods that cause you trouble and limit or avoid them according to how you feel. Eat whole grains and much fruits and vegetables. Have your white meat cooked. Eat at regular times each day and divide your food into 5-6 small meals a day. But firstly, double-check for pregnancy, just to be on the safe side.