An attack for me is when my tummy is so bloated and tight it hurts to touch it, yet there is no relief from the gas that is expelled - and there is a lot - and I am unable to have a regular bm - only rabbit pellets if anything. I feel full and really miserable. If it is severe, there is a lot of pain involved as well.
A mild attack is just that - a milder version of what I described above. Sometimes there is an added urgency like I just HAVE to go and then - nothing. Very uncomfortable.
However, I'm pretty stable right now and very thankful for that!!