What ever works for you mate, if you feel yourself getting faster and stronger then its far from a negative routine, although im not an expert i would NOT advise you over-do it but keep chipping away mate get those times down and youl feel proud of yourself!
Longer runs are important for your general fitness, but also try and replicate the things that you are going to be tested on. Remember that after the PJFT (which you seem to be training for) you'll have a PRMC. So the sooner you start training for that the better... get the 3 milers in, press-ups, sit-ups, pull-ups etc.
None of that will harm your training for your PJFT either.