It sounds like either one or both of the following:
1) you did not go to a state of the art physician;
2) you need more sessions to increase density.
No hair transplant is a one session ordeal.
That's why it's better to hold onto the hair you have as long as possible and then only get hair transplants when you have the time and money to commit.
It's a rich man's activity, like mountain climbing. How many boys from the 'hood have climbed mount Everest, though they probably could physically?
You have to have time and money to devote to a successful hair transplant and it takes a good 3 years (one session every 10-12 months).
Right now, at 34, I just stay away from test and go with deca/NPP and I make sure I take topical spiro and minox/azelaic acid twice per day.