teen angst

So, i've figured out that the reason i have been feeling anxious so very often in the last little while has a directly negative correlation to the amount that i let myself cry. i used to cry over every little thing and was never plagued by anxiety. i haven't let myself cry for over a year and now, i am repeatedly anxious until i have a huge breakdown and freak out at my family and have a huge cryfest over nothing.
Also, i've been smoking cigarettes to try to alleviate this feeling, but i just can't do that anymore. my lungs are dying and i may have given myself bronchitis or even pneumonia. So, as per Nathan's advice on dealing with it, i've tried to distinguish what it is that is making me anxious the most. Of course i KNOW what it is. i know exactly how far back the anxiety started and i know exactly what i am usually thinking of when it comes. i am 99% sure that i know what triggered it in the first place and 99% sure that i know why it keeps coming back. but now that i know, what am i supposed to do about it?