Exhaust Question

[Nj2k2k1]

Recently while driving, I noticed my air conditioning wasn't working too great so I decided to pull over and check the coolant. What I noticed was that my coolant was bubbling and it seemed a little low. I had some in my trunk so I kept filling it...and it would eat some of it up and continue to bubble. I kept adding coolant until it stopped bubbling and the car ran fine. Now, when I start my car sometimes, exhaust smoke comes out and it continues to come out for at least a couple of minutes (which Im pretty sure is longer than it should).

Anyone know of any specific problems I might have, or if there is any real problem?

Any help would be greatly appreciated

-Jared