Why is my stomach rumbling?

Hello doctor,

I am a 13-year-old female and my height is 5 feet. I weigh about 106 pounds. I have been having stomach issues. The main issue is stomach rumbling. It happens when I wake up, after eating almost anything and before I sleep. I have tried skipping one of the meals but to no avail. It still causes the same result the best working being no dinner but having breakfast and lunch. I very rarely have soda, fast food items, or frozen dinners. I have searched up for gassy foods to avoid for example broccoli) but it still does not help. I sometimes do 35 to 45 minutes of crunches, which kind of help. Sometimes it feels uncomfortable and hurts a little but that is not my biggest concern. The rumbling starts at about 10 o' clock onwards. It is so embarrassing to hear it go off every day during my class. Nobody is rude or talks about it, but still, it is distracting and annoying to deal with. I do not want to be dependant on gas pills unless there is literally nothing else to do. I have no food allergies, I am not lactose intolerant, and I am not a vegetarian. I eat raw almonds daily, so I do get a good amount of fiber. Same with graham crackers, is that a bad thing to eat? I am an active swimmer, usually one hour to 45 minutes four days a week. I walk my dog for about 30 minutes. 1. Are there any foods or diets to suggest? 2. Anything to stay away from? 3. Anything to eat more of? 4. Any exercises that would help? 5. Should I be asking a doctor this?