I Cant Fall Asleep, Please Help

ok, I m 15 and lately i can t fall asleep. during the day i am exhausted and when i get home I m still tired but i cant sleep no matter how hard i try. i get in bed at 10 and usually don t fall asleep until 2 or even as late as 4 in the morning, i have to get up at 6 and i am so tired. what could cause this? could i be depressed? i hardly ever have soda or coffee so idk where i d get caffeine and i exercise everyday after school (basketball softball) I have two 7pg essays due in a week and 5 quiz s between now and winter break. So i cant cut back on school, but that isn t going to be the reason i am not sleeping because i haven t been able to sleep in months. i don t drink caffeine drinks, either Vitamin Water or regular water, i exercise 2-3 hours a day and i am physically exhausted at night i just cant sleep. i listen to Andare by Ludovico Einaudi every night on repeat before i go to bed, it is an amazing classical song, but i still cant sleep! I m not sure if i am depressed or not, but ppl ask me if i am ok all the time, my friends think i might be. and once again, i don t have caffeine drinks, at all, it isnt good for your body and i have too many sports that i need to be in shape for