I remember when I was in the same position as you. 
It's actually kind of hard to explain, there are positives and negatives, like with anything.
I suppose the first thing to say, would be that it feels as great as you imagine it would, to be bigger and heavier, it's amazing and can be quite addictive, causing you to consider going past your initial goals.
However, you do also feel the other stuff too, slower, more lethargic, less energy, but that may just be my sedantary lifestyle, I imagine if you stayed somewhat fit it would be less dramatic.
Its also not something which you become certain about, I still have days where I doubt it, and wonder if i should try going back, but the experience is one i will never forget.
Outside of that, you don't really notice it that much, I mean i still feel i'm the same person I was when I was thinner, and no one has really treated me differently, although that probably comes with the more you gain.
Anyway, I hope I helped give you some idea of what its like.
It's actually kind of hard to explain, there are positives and negatives, like with anything.
I suppose the first thing to say, would be that it feels as great as you imagine it would, to be bigger and heavier, it's amazing and can be quite addictive, causing you to consider going past your initial goals.
However, you do also feel the other stuff too, slower, more lethargic, less energy, but that may just be my sedantary lifestyle, I imagine if you stayed somewhat fit it would be less dramatic.
Its also not something which you become certain about, I still have days where I doubt it, and wonder if i should try going back, but the experience is one i will never forget.
Outside of that, you don't really notice it that much, I mean i still feel i'm the same person I was when I was thinner, and no one has really treated me differently, although that probably comes with the more you gain.
Anyway, I hope I helped give you some idea of what its like.
12 years