One thing that you need to be careful with is that the weight you are putting on is actually coming in as muscle or water weight. Check your body fat after extreme weight gains.
Also, be patient. It tokk me about 6 years to go from 135lbs to 190 lbs. You learn how to eat over time. Instead of asking everybody in the world the same question, start listening to your body. Remember that if you ask the same question to ten guys, they will all give you different answers. They are not neccarily wrong, but they may not be right for you.
Get yourself a good trainer or spotter in the gym and cycle your workouts to include some overloading. Be careful because your joints will suffer with too much overload. Then you will fell like an old man by the time you reach 30.
Remember that most supplements are junk. I have researched this area for years. The things that usually work are harmful to your body. I was a Pro Wrestler for two years. I got to know Stone Cold Steve Austin. He is on pain killers and steroids. I had a talk with him about that. He said something that made a lot of sense. He gets paid millions of dollars a year for doing what he does. So for him, the benefits outway the risks. So if you sacrafice your health for no money, and later in life you suffer from bad health, with no money; what are the benfits?
Good luck in the future and keep us posted with your progress.