Hey Loco - well done! The warm weather makes it so much harder, doesn't it.. first you had the wind and now this, hehe
Take it v easy in warm weather, your body heats about 10 degrees when you run so you have to remember that if it's 20 degrees outside, you'll feel like it's 30. Dress light and try to stay in the shade as much as you can.
With regards to your asthma, yes, work on your breathing. Long and steady breaths in and out and really focus on breathing out - you need to empty your lungs properly so that you can get fresh air in again! Make sure you carry your inhaler with you and you'll probably notice that it depends on the weather a lot - I think today it was a bit humid, air is kind of heavy and there's probably a lot of pollen in air, ie. less oxygen so it makes breathing harder. I have exercise induced asthma myself and it completely depends on the weather how I feel. Cold or humid weather are the worst. I take my (blue) inhaler before running always in the winter time and in the summer if it's really humid or if there's a lot of pollen in the air. Otherwise I wouldn't be able to run! If you find it bothers you regularly, talk to your doctor. I used to get really bad chest pains after running - first I'd find it difficult to breathe while running, sometimes had to stop, and then afterwards I'd be in agony for hours.
Also, I've seen lots of people who have had asthma in the past and even if they've had no symptoms for years, it might start bothering them again when they first start running. Usually it's not a big problem, once their lungs strenghten and get used to it, they're fine but it might be worse in certain weather conditions, as I said above.
Anyway, hope it won't give you too much bother over the next few weeks!
Let us know how you get on, you're running good distances now so well done so far!