Adam
There are two points to make here. First, that is a very good group. What distance were you shooting? Since the group is a little high, you may want to lower the rear sight a bit. How much, if any, will depend on the distance to the target. To explain this, any handgun will only hit exactly at two distances. For example, on my Colt Commander, the first zero is at about 4.5 yards (from 0 to 4.5 yards the bullet will be low and rising) and the final zero is at 25 yards. Between 4.5 yards and 25 yards the bullet rises, reaches the top of the trajectory and begins to fall. The distances that I have mentioned above will not be the same for any other gun and ammo combination. I may be wrong, but I think that your P99 is factory sighted in at 25 yards so you results will be similar.
If you want to determine the exact ballistics of you round send me a PM and I will give you the info that I will need to do the calculations.
It is a good idea fire your gun from 18" and out until you find the first zero point and then continue all the way to 25 yards to find the second (the real one) zero. If you ever had to take a precision shot (a hostage situation for example) at, say, 15 yards it would be good to know where the bullet will strike. Sadly, very few people bother to find out where the gun shoots and simply adjust the sights for some fixed distance that they most often shoot.
The second point that i want to make is on your question of speed. You can try to push yourself but it will rarely work. There is an old comment from one of my instructors that says that when you get smooth that speed will come naturally. I would suggest that you spend a lot more time dry firing. This will help a lot.