Part of it will just require consistent practice and time. Like lifting weights. You can't expect to double your bench press over night or within a month.. It takes dedicated work over a long period of time. When I first picked up my trumpet <2 years ago I was lucky to hit a D or E on the staff. Last night I played a double octave C scale from below the staff to above the staff. This is not high as defined before... High note trumpet playing is when you start seeing the paint peel off the wall e.g. Maynard Ferguson.
The higher notes will come with time, just be patient.