Bloating is a sensation of fullness from increased visceral sensation common to IBS. It can be triggered by variety of things including foods, stress or simply the act of eating which stimulates the Gastrocolic Reflex .
One of the goals of Heather's EFI diet (Eating for IBS) is to remove trigger foods which produce IBS symptoms such as bloating.
There is a description of bloating and possible mechanisms in the British Gastroenterology Society's Guidelines on the irritable bowel syndrome: mechanisms and practical management in Section 4.6 on page 1779. Note that is says sufferers typically report a worsening of bloating as the day progresses, particularly after meals, with the symptom usually improving or disappearing overnight. The bloating symptoms you described are common.
All of us are looking for way to manage bloating
-------------------- STABLE: ♂, IBS-D 50+ years - Science of IBS