My first time using this app..help?

This is my first time ever using this app. I am 22 yrs old and already have 2 daughters from a previous relationship but things didn't work. Then i met my husband  :-D. We will be married for a year in march. Anyway we decided we want a baby together and have been trying for awhile. So far no luck!.. And i guess my question is how many of you got pregnant your first time using this app? And also i OV'd the 25th of this month and have been very active up until today.. How accurate is this app??