Trying to get pregnant

Trying to get pregnant been charting my temp but i have noticed i am not ovulating and i have read that you can test positive on a ovulating kit and not release an egg this is so not fair i have been trying for a long time and i have 4 older boys i had no problems getting pregnant then why now i know that i had to make an appointment to see a ob and find out what is going on i have also tried herbs b6 , vitex ect nothing has helped :(