I ovulated on the 17th of April on cd 12 i had on cd 8,9,11,13 what are my chances of getting pregnant?

this was my first cycle using an opk. also can some one tell how many days am i dpo. because i am confused.also i am having alot of cramping. i never have cramps even with aunt flo. i am also having pain on the ovary where i ovulated from. lil bit of nausea. very moody. lightheaded, dizzy, and extremely tired all the time the only thing there is no sore bb's. every once in a while a little sharp shooting pain. i took a prenancy test on cd 16,17,18,19,20,21,22 all negative go figure temputare spike on cd 20. extreme cramping from then on until now. this is not my first pregnancy i have 5 other children ages 24,21,18,17,16, had an blighted ovam last year so really hoping that this is the one. you you guys help.