Unfortunately there is no "correct" form of resistance training. No matter what anyone says, there is no one way that is proven to be the most effective form of training for building muscle mass. A while ago I wrote an article entitled "The ONLY Way To Train" which deals with the common misconception that there is one (and only one) way to train.
The number one factor to ask yourself is - have you received the desired results (at the desired rate) by training this way? Have you compared this method of training to others and is this more effective in order to achieve your goals? If not, some changes are in order.
You will notice that there is a very common theme throughout this website...intensity. Intensity is what I believe to be the number one factor to stimulate consistent hypertrophy and strength gains. Looking at your training approach, it seems that set 1 is intense as you are working to your maximum. But the following sets seem to be more of a cool-down. How are you stimulating your body to change in the following sets as you decrease the working load? I also recommend you read my article "The Art Of Adaptation" which discusses why intensity is a key factor in your training regime.
Perform a website search for "intensity" and you will find a number of articles discussing this topic. I (and the other professionals on this site) strongly believe that training maximally is a crucial element for healthy people wanting to instil big changes in their physique.