Answer:
hi hun!
i think its definitely possible to lose 15 lbs by june. Some tips i can think of are:
Eat clean, eat often, & eat enough especially since youre still a growing girl. some people dont know that theyre net caloric intake might be too low. & please make sure you have enough carbs & protein to fuel your exercises/sports!
Hydrate, hydrate, hydrate. For athletes, i know that powerade, gatorade, & such are popular, but i dont recommend them because of their sugar content. WATER is #1 for me, but another option is coconut water :)
Rest! REST! RESSST! dont over-exert your body.
thats all i can think of right now! i hope it helps. let me know how everything works out for you <3