Hi all,
New runner and new to site - Appreciate any help you can offer! 
I used to be a smoker (1 year clean) and I'm still over weight (around 210 Lbs) so I suspected running would not come easy. I've sorted out the running shoe dilemma, shin splint debacle and technical clothing issues but I can't seem to get comfortable with my lungs.
I have been doing intervals religiously for 3 months (3 mins walk: 1 min run for 30 mins and have been decreasing the walk time gradually) and I am now at the part where I have to increase my running time by 30 seconds per week.
I was told this method would kick start my cardiovascular system and my body would understand and at some point begin to accept what I'm doing but I feel like I will not be able to survive the increase in the run time because I'm already so winded at the 1 minute (especially near the middle and end of the 30 min set). I am concentrating on the control of my breathing and my form is good.
Is there something I can do to check that my lungs are in condition for this sort of thing? Is this common for new runners?
Please help! I really love running but I feel like I'm not getting to the point I need to be at at this stage.
Thanks!