I got together with my good bud and he made a 6 week bionic arms program. We took Prolab N-large II protein/mass builder and NO-Explode. In 6 weeks I added over 10lbs of upper body mass. We played basketball for leg days... I gained 50lbs to my bench and looked great. I wore nuthin but sweatshirts the entire 6 weeks and when i was done and went back to t-shirts and cutoffs i couldnt convince my own mom i wasnt taking steroids. I'm actually gonna start this again soon and include legs. I'd use a lot more dumbells as well in your current workout. Alternate incline,decline and flat with both bench and dumbells. Also 8-10 reps should be first set and go up 5lbs each time with the dumbells. I usually keep doin that until i can only do 4. Alot of heavy weight to failure is what we did in our 6 week program, that will build mass quickly. Also do a lot of isolated lifts, ie. dont bench, use dumbells or just use bench as a warm up. Do military press as a warm up for isolated shoulder exercises. Pretty much do something that works the whole area first to warm it up, then do the heavy stuff in isolation of 1 or 2 muscles. And last but not least, eat 4000cal a day atleast. and make it good well balanced food. I usually eat everything in sight, but try to make sure i get a lot of carbs(energy) and as much lean protein as possible. You pretty much need 6 meals a day and force yourself to eat more and more and more.
At 16 i was 6' to 6'1" 130lbs, This spring at 18 i was 6'2" 195lbs and i didnt start lifting until i was 17, and only got serious last fall. You can do it, but you just gotta live to get big. I wanna be 210lbs and under 10% BF before next summer.