Everyone's IBS is different & with respect, needs a different approach to resolve it. A Gyna' did once also tell me it can be hormone related/cyclical which resonated with me. Post menopause I stopped suffering!
In your shoes, if these symptoms are new to you, please see your GP to rule out anything else.
Some sufferers find high fibre helps, for others it makes matters worse.
IBS is most unpleasant so I hope you find a way forward which will be helpful for you. It could be a long haul though. Take care & try a hot water bottle on your belly and a lie down. That was helpful to me.