Gastric Pain

I had gastric problem since 9 years old - Pri 3.
I remembered it was during English Class and I was having very bad pain and it was so unbearable that I nearly fainted.
My form teacher carried me to the nearest polyclinic for consultation.
She then brought me back to school and called my mum to fetch me home.

How I got gastric pain at such a young age?
I dont know why but since then I've this problem till now...........

Today after lunch I felt the pain is coming back, I knew this agony will persist for a few days .....
I'm just worried that it'll be so unbearable that I cant sleep tonight.
RY suspected that this is due to the anti-biotic given after my surgery - supposed to take 2 times a day for a week.

I'd done scooping 2 years ago and a kind of bacteria was found and I was told to start a couse of anti-biotics to kill them.  As I was planning to get preggy, I ignored this problem.
Since I've m/c, maybe it's time I go to doc to re-visit this gastric issue.