help improving my running ASAP!? Please!...

Zero2hero2013

ok, so i really want to get into running, but i find it quite boring, this last week i have been pushing myself to get on the treadmill, with the goal of running outside eventually, i have a friend who can run 3 miles outside and currently i couldn't achieve that so feel embarrassed. i want to catch him up so i can train with him.

my current fitness levels are, ex smoker of 3 months ago, (heavy smoker), never done much cardio, recently been attacking it hard.

my best session to date which was yesterday was 17.5 mins continuous jogging/running achieving 2 miles on the treadmill.

my current training is as follows

monday: chest at lunch time(12-1.30pm), long slow duration evening (5pm after work)
tuesday: back workout at lunchtime, intervals in the evening,
wed: rest
thursday: shoulders at lunch, long slow in the evening
friday, intervals at lunch , legs in the evening.


my real question is, how hard should i push myself how often can i train? would it be worth doing 2 full body workouts and adding more cardio sessions instead? i really want to whoop my cardio into the best shape, a complete overhaul as quickly as possible so i can get back to strength/ hypertrophy training while maintaining my new abilities.

also i am trying to burn off all excess fat so i can become as lean as possible, currently weigh around 91kf at 14% bodyfat, hoping to get down to 85kg in the next 8 weeks. maintaing as much of the muscle as possible, but ultimately focused on improving my fitness and endurance in term sof strength and cardio.