Light line and then no line?

Chelsea

Advice please! This is my first cycle ttc. I came off bc, 3 days later had my withdraw bleed which lasted for 4 days. I started opk on cycle day 7 and got a lightish test line, definitely not positive. Then tested cycle day 8, again a lightish test line but darker. I tested today in the morning and evening and there was no test line at all. Any idea why it would disappear or what this means? Did I maybe already ovulate? So confused!