Typical teen training

Yeah, 40 reps is plenty. One day, try 4 x 1-3 reps with 155, resting 2 min between sets. Try other equipements, try pullovers, try chin-ups!!!
That said, if you train chest and bi's 3 days straight, 1 day rest, and start again, no wonder you find 135 pretty tiring. I did chest y/day, and there's no way I gonna lie down on a bench today, NO WAY! I did bi's as well, and I still struggle to pick the pan with the eggs off the cooker this morning.
Time to vary my friend:
Day 1: Bench Press (3x8) Pullover (3x8) Dumbell Flies (3x8) Barbell Curl (3x8)
Day 2: Squat (3x8) Romanian Deadlift (3x8) Leg Press (3x8) Abs Crunch or/and decline bench situps (3x20)
Day 3: Wide grip chin ups (3xwhat you can) Barbell Row (3x8) Seated Cable Row (3x8) Dips (3xwhatever you can) Narrow Grip Bench Press (3x8)
Rest
If your dinner is kinda much earlier than bedtime, take your shake before you hit the sack, in my opinion, it'll help you more since you can't afford 3 scoops a day, 1 scoop will do. Before you train, try to fit in something energetic, like bananas...
If you have your dinner more than 2 hours after your workout, try the shake straight after the workout, and drink a pint of milk before bed instead. If you have the shake after workout, use water. If before bed, use milk.
Squat/DL : start LIGHT! 135 max. start with empty bar to warm up, watch your form, thnk about what muscle are used to move up/down, feel them, squeeze them while training without load. A Romanian deadlift is great for hamstring. You bend the knees a bit, stick your ass out the back, back slightly arched, bend at the hip, grab the bar, pull your shoulders back, and pull with your ass/hamstring till you're standing up. Keep the bar as close as possible to your legs.
Chin Ups/Dips ... Maybe you can't manage them with your own weight, maybe there's an assisted machine handy. If not, do seated dips: feet on a bench, hands on another, and lower your ass off the bench till your tri are parallel to the floor.
PS: Maybe you don't go to the gym yet and train at home. hang a bar somewhere for chinups and build a wooden rack for your squats. All it takes is a pair of 4x4 at and slight angle, far enough appart for you to stand in between and grab the bar comfortably, and a few thick pins at a few different eights to hang the bar onto. As for the cable row, well, I guess you'd have to do more chinups and barbell row instead
Be creative, it takes the boredom of training away, and good luck!