I have a hypersensitive, IBS-C gut. I eat zero and trace FODMAPs (after much experimenting with the greater variety of low FODMAP foods). I use the Monash University FODMAP app as they have measured lots of different foods.

I also eat grain-free and lactose free milk products (mostly nonfat milk).

(Note that if you eat at a single meal that has five FODMAP foods at the low FODMAP levels, they could still add up to being over the threshold for you.)

The Monash-listed zero/trace FODMAP foods saved me. Also, apple cider vinegar with my three main meals -- I guess I needed a more acid environment. There is some literature on how apple cider vinegar can help IBS. The vinegar actually seemed like the last piece of the puzzle for me.

I do other things -- a peppermint oil pill to settle my gut before a meal (studies on that), animal fat as it is a trigger (I focus on oil and a small quantity of some nuts).

Relaxing/destressing is huge too. There is an app called Mahana. The first segment is free and is great. Give it a try.

Belly-breathing, pushing out your diaphragm when you take a breath, is very calming. For me, the stress-gut connection is very strong.

Good luck! Keep at it and experiment, experiment. Hopefully you won't have to be terribly restrictive in your diet.