When i eat, i feel so full and discomfort with passing out of a lot of gas. after i use the toilet, i feel dizzy and weak. help!

IBS: you have what we called here in the USA irritable bowel syndrome, European might call it spastic colon.. the full bloating feeling is typical. the straining associated with the bowel movement, or the sudden release of pressure will create the feeling of dizziness and weakness. first avoid food that caused this regardless how much you like it. eat multiple small meals. meditate, relax, and exercise