The majority of these responses to the belief that lifting weights at your age will "stunt your growth are incorrect". Assuming you take the smart approach you need to work on your form WITHOUT weights to begin with in order to safely workout without the risk of doing harm to yourself. Lifting weights isn't the only thing as well. You could go to the gym everyday and eat like shit and you won't see a SINGLE gain, you might notice your muscles get harder but there won't be any significant gains occuring. It takes about a year or so of proper dieting and routine working out in order for your aesthetics to show in terms of muscle mass(depending on your genes).
Here's some proper dieting/lifting tips.
1. Regardless of what people say as long as you get your calories to meet your goal each day, it doesn't really matter if you skip breakfast or eat small meals consistantly or even just do 2 big meals.
2. Protein shakes themselves are expensive, your best bet would be to go on amazon and order my personal favorite "Optimum Nutrition Gold Standard Whey protein". Your grams of protein should equal or at least come close to your bodyweight in grams.
ex: I weigh 164 pounds, i should try to eat 164 grams of protein every day in a spread out manner in order to correctly gain mass. However, don't load up on just protein shakes, buy chicken breasts, organic fish/tuna and use those as methods to attain proten.
3. Count your calories, Macros, etc.
4. Don't try to show off, the fact that youre in the gym shows enough so don't try to impress people by lifting too much weight, we all started somewhere.
anything else shoot me a pm and I'll message you back.
EDIT: Read this, it will teach you EVERYTHING you need to know about how your body works, what working out routines work well, and dieting tips.
http://liamrosen.com/fitness.html