Can anyone help?

My next period is due for 40 days... Over the past week I've been taking ovulation tests (I'm new to this so I don't know when to take them other when glow says I'm more likely to concieve- at the moment it says 3% but this based on my very irregular periods.) I have taken these tests for the last week and some of them are blank and others are ghost lining- I can see a vvvfl; what do I do? I've been having sex and using conceive plus; but I don't know if I'm actually close to ovulating or not. I'm 22 and this is the first time I've tried for a baby so anything I'm doing wrong- please tell me; and all advice is welcome. I'm also taking pregnacare prenatal vitamins. Thanks xox