Ok, I'm trying not to get all hysterical, but period is late by 1-3 days (not sure of exact OV date this month), and had 3 BFNs in last week. I am using the internet cheapies for the first time.
I'm not proud of this first bit, but rooted through the bin for my PG test I did this morning, to just check it was still BFN and it had a faint line on it. I'd thrown it in the bin in disgust this morning after nothing showed straight away. I presumed it would be an evap line, but after a little internet research have read that evaporation lines are usually colourless 
Just tested again, and read the instructions properly and it said to check results within 5 minutes and after that they could be void. At about 5 mins a faint pink line appeared again. Am going a bit out of my mind here... can anyone tell me anything? Or just hold my hand til ds wakes up and I can go to the shop and buy an expensive test?