I dont know why i dont see gainz?

First let me start by telling you that i am 16 y/o, 5ft8 and i weigh 64kg/141pounds.I have been "hitting" the gym for 8-9 months now.Because of school i was going to the gym 3 times a week and the other days i had swimming lessons.My question is: Why i havent seen gains?i feel like all this 8 months i was wasting my time...(i didnt count my calories,protein etc. because i dont have knowledge about nutrition)i dont know what to do...I have lost all motivation.I saw some YT videos with transformations and people get a really nice body in 3 months while i dont even look close to that.I need help asap :(