I'm mad at my mom for getting me sick
What did she do to get you sick?
She took me for a walk in the rain and  didn't stop smoking.
It is wrong to smoke around kids and possibly get them sick. You should go see a doctor to see if there are any lasting issues that might effect your health.
I know, I might have to now.
Your mom messed up and since it's her fault, ask her to take you to get a check up. It seems like a minor illness, but still, tell your mom what she did was wrong and help her to stop smoking.