Emergency Cerclage (was it a good idea)

i've ben stressed out through out my pregnancy; with my job, my parents, and the father. so with that i've been getting pain here and there which was told to me was normal. But one day i had difficulty walking without being in pain so i opted to go to the ER. i thought i pulled a muscle (like my groin or something) but the doc said  i was having contractions then asked me if i am. WHAT THE HELL IS CONTRACTIONS cuz this is my first baby. anyway, they said even at 22 wks i was dialated almost 2 cm so they scared me into having first an amnio synthesis, and then  a cerclage. now i'm worried about infection b/c they never gave me antibotics like i've read in everyone elses case . how do i know its a success - if i have the baby - and can anyone tell me what contractions are cuz not even my mother who had 6 kids can tell me?