I Am In The Military And Part Of Our Pt

I am in the military and part of our pt test is maximum push ups within two minutes. I am trying to improve my score, however, I can't seem to get that much more then 50-55. I start to basically do one arm push ups because my right arm goes numb and is not that responsive I work out on a daily basis and I have seen the strength in my arms chest and shoulders rise by the amount of weight I can lift but can't improve my arms endurance. It isn't very painful but my right shoulder pops when doing the push ups, and when I look at my self in the mirror my left shoulder is slightly higher then my right. How should I handle the situation? Thank you for your time in advance.