Hi ksupreet
I think it would be worth having some allergy tests done. Some GPs can do these skin tests themselves. They drop various allergens onto your skin then wait to see the reaction.
Does your home have a damp problem? That can create terrible lung problems. If you feel better when you're outside, it may well be something in your home which is causing your problems.
I tried Singulair for a while. They say that if it doesn't work within the first month, it won't be worthwhile taking. Best ask your GP about the question of taking Singulair whilst pregnant.
You're right in saying that allergy can cause asthma. My worst enemy is house dust, also inhaled strong perfumes like air freshener.
At 147lbs I guess you're a bit overweight but wouldn't imagine it significant enough to cause breathing difficulties.
Does your doctors surgery have an asthma nurse? I've often found them more helpful than doctors.
Hope you find some solutions soon.
Best wishes.
Lidia