go see specialist and get a colonscopy to see what wrong inside your stomach.

there are too many sickness related to gastric.

there is nothing to be afraid. Malaysian tends to easily diagnosed with gastric due to unhealthy foods consumptions and poor diet culture. That why, it is always crowded in the gastroentrologist section.

If you sickness still presist or got worse, advisable to see specialist. Especially if you have insurance covering your cost.

just try drink warm plain water and eat plain food for a while. Will ease a bit of your pain.