I was having the same problem 2 years ago. Anything I ate, no matter what it was, the quantity, when I ate - I would bloat instantly and severely. I was diagnosed with IBS (irritable bowel syndrome). I also gained weight.
Exercising helps me a little and I find that when I don't eat, or wake up in the morning I am not bloated. Get your doctor to look further into this. Good luck
Unfortunately no medication worked for me. I also tried natural remedies to no avail. I rely solely on exercise and a high fiber diet, but even that doesn't relieve my bloating majority of the time. Also, try and find ways to manage/ minimize stress - this is also a huge factor.
I'm still in the process of finding multiple opinions from different doctors. It's a shame there is no cure for IBS