even at18 and looking at your weight 5 times a week for 2 .5 hours is too much.
I would stick to a good clean diet , chicken fish etc, slow releae carbs-brown rice, pasta , sweet potatoes, plenty of vegetables and a good fats supplement such as udos choice.
For supplements look at creatine products, taking l possibly, BCAAs and SLOW RELEASE protein blend to be consumed away from posttraining After workout take a carb /protein drink which could be -simple sugar- and whey.with BCAAs 10 gm added to the drink.
Caffeine based pre workout drinks are ok but dont become dependant on them and it may be that the jacked is giving you the stimulus to go 2.5 hours.Even a full body work out shouldnt last that amount of time.
Take a look at your training programme and narrow it down to basic exercises concentrating on large muscle groups -chest , back, legs ie bench press, squats, deadlifts. For get tris and biceps because you will be working these indirectly.
Reduce your programme to 3 sessions per week of about 1 hour -1.5
Keep cardio to a minimum but dont forget to warm up .You could do a warm up set using light weight and high reps on each of the above exercises before you commence proper.
Eat well and get a good nights sleep .
Steroids otc or not -forget them -you are too young .