Hey there Mooshie. I used an OPK this month. I just bought it from Coles or Woolies for $20. I used the Fortel which is in a greeny/bluey box and there are 5 tests in a box with an instruction sheet. So depending on how many days in you cycle to when you start testing. I have a 28 day cycle and started testing on Day 11 just to be sure. The instruction sheet says to start testing on day 12 for a 28 day cycle...... I was just a bit eager to start!!!

Ok So Mon, Tues I got -ive results. On Wednesday morning I got a 2nd line which was dark but not as dark as the control line so I retested that night at about 8pm and it was very dark. The instructions say to test the same time everyday anytime between 10am and 8pm. Once you have got the line as dark as the test line it means you are going to ovulate anytime between 6-24 hours. In my case I then tested on Thursday at 11am, same time as the others and got -ive again so I guess my LH surge had been meaning I would have ovulated 6-24hours after 8pm on the Wednesday night. Hubby flew out to work at lunchtime on the Thursday so I Bd'd Wednesday night and Thursday before he left, so hopefully we have caught it, but if I ovulated the full 24 hours later I guess I wouldnt have!!! I hope I am making sense.

You would generally only need one box for the month Mooshie.

Well I hope this has helped you and that I havent rambled on toooooo much.

Take Care