For a few months now I'm suffering pain in my stomach after every main meal I eat. My meals are healthy and I have the right portions. Do anyone else suffer from this and know what it could mean.
You should probably see a doctor. It could be something simple that needs to be treated now to avoid complications.
is there anything you've changed about what you eat in the past few months? A new supplement? A new spice? A new brand? More dairy? More raw veggies? Some things like raw broccoli can cause some people gas... Did you change water drinking habits? To much water during a meal might affect digestion...
I might try eliminating certain foods one by one, especially anything that is a common allergen or trigger for sensitive stomachs. But see a doctor if at all possible.
You may have some sort of mild food intolerance, try experimenting with different foods to see if some make you ache worse than others. Regardless, this may be a question for a doctor and not a workout forum.