IBS for a youg person is very difficult. My IBS started in my teens. The name for it then was spastic bowel and its cause was thought to be in your head. We are much further ahead now.
Unfortunately there are all sorts of individuals willing to sell you untested products and services - snake oil - to help manage your IBS. This is truely disappointing.
Have you seen a doctor and discussed your symptoms with him? If you have what tests have been done?
-------------------- STABLE: ♂, IBS-D 50+ years - Science of IBS