Thanks for using the forum.
It is great that you want to eat healthy! An important rule when eating healthy and dieting is that you do everything in moderation. If you don't eat, you will feel hungry and be more likely to go off your diet. If you eat small amounts of healthy food throughout the day you will find that you are not as hungry and will be less likely to snack on the unhealthy stuff.
I am not sure how old you are. If you rely on your mom for food shopping (because you don't drive, or don't work) then I recommend speaking with her again about more fruits and vegetables. Explain why you want to eat healthy, if your mom knows that you are not feeling well after eating junk food she might be more likely to take your requests seriously. Ask if you can go with her to the store to make the healthy choices for yourself.
Always start your day off with breakfast. Try to have something with some protein to help you feel full longer. Some suggestions would be egg white omelet with fresh veggies, yogurt and fruit, peanut butter (if no allergies) on apple slices. Make sure to drink plenty of water throughout the day. I recommend carrying a water bottle with you all day to drink from. If you want a snack during the day, try to stick to something healthy like carrots and hummus, a banana, a handful of nuts...
In addition to a healthy, balanced diet, exercise is important for health and weight loss. You don't have to go to the gym if it is too time consuming. Get out and walk, do an exercise DVD. There are also workouts for almost every fitness level available as apps for smart phones, and through iTunes. You can even take fitness DVDs out of most libraries. Try to set aside a little time everyday to exercise. Even if you just walk for 1/2 an hour it can make a big difference.
These are just a few suggestions. If you want a full diet plan, you could speak with your doctor. They will be able to direct you to the best diet plan for you.