Hi Shana,
I'm sorry you are having shin splint pain, I know first hand how that feels. Let me ask you a few questions. Have you ever ran before? How much are you doing at the track? Shin splints are usually caused by trying to do too much, too soon...which is a common mistake people make when starting a program because of their frustration and their desire to make an instant change with instant results.
Please don't fall into this trap. Start out slow, walking first, build up to a slow jog, and stretching is very important AFTER you run or walk. Don't neglect that part of it, set aside some time for slow stretching. Don't do the "bouncy" type of stretch, slow even gradual stretches are best and will help prevent injury.
If you don't have access to a gym for weights, or if you prefer, you can do some body weight exercises at home. Just the basics to get started, for example: Ab crunches, push ups ("girl style" is fine until build more strength), leg lifts, bicycle crunches, etc. There are some great examples of floor exercises on this site in the Exercises section.
Don't try to run anymore until your shin splints are healed. The link that Lesplease provided shows some effective treatment and preventative measure to take to avoid them in the future.
Also, to really lose weight and make lasting changes, you need to have a healthy balance of DIET, WEIGHTS, CARDIO. There are some really great people here who can direct you in these areas. I am not an expert, or professional trainer or nutritionist, but there are many here who are who can address those issues and help you find the right balance.
What you eat, how much carbs/protein you eat and when you eat it are crucial to successful weight loss (I had to learn this the hard way!).
Please don't give up, don't hesitate to ask questions, we want to help! I wish you much success in all you are trying to achieve

Hang in there, keep working hard!