A.A.
Is it possible for you to quit work so you can take care of your body and your 2 year old? I know my asthma kicks up a lot when I'm over-stressed and fatigued. I would also look into a homeopathic or naturopathic doctor to find natural remedies that are good for you and the baby.
I believe there are also some acupuncturists who work with pregnant mamas. They have been a great source of healing when I had recurring bronchitis along with my asthma one year. When I finally gave up the prescription drugs and only used herbs and acupuncture, I stopped the cycle of the bronchitis.
One last thought, especially while you have a cold, is chest rubs using Vicks or a new product by "All Terrain" that is basically the natural version of Vicks. My husband has put me into a peaceful sleep many times that way.
I hope you feel better soon!