I've had an ileostomy for 11 years. Rectum is removed....so no problems there. I eat whatever I want, even popcorn and nuts in moderation. I don't recommend either in the beginning. Foods such as carrots come out the same way they went in. Raw vegetables and greens make plenty of gas and should always be eaten in moderation as well. Beano is terrific to fight the gas, and yes, the bag does expand. Foods that will block you are anything with skin!!! Peel tomatoes always, dried beans (especially large butterbeans are killer). I blocked the first time on grapes!!! Second time on English peas, third time on pulled pork barbecue....I eat them still, but in moderation and I find eating potatoes helps me a lot. The starch seems to break food down or something. In the beginning, the stoma and opening are so small that blockage is almost a given at some time, so don't be so scared, okay? You'll know and they'll give you IV fluids until it passes. Once it happens, it (well in my case) it stretches the stoma or the channel leading to it...I haven't blocked in over 6 years.
I know you're afraid, with every reason to be. But I had much more trouble BEFORE my ostomy than afterwards. It will be okay, I promise. Once you get over the fear, and you will, you'll find what works best for you. For instance, I find that milk makes me very liquid and I avoid it if I'm going out, but have it if I'm prepared. Also, did they tell you that your stoma will move around???? Boy, that freaked me out!!! LOL
If there's anything you want to ask, please don't hesitate. There's no subject too personal, okay?
Good luck, speedy recovery, and the start of your new life...
Your ostomy sister, BEG