Driving myself mad - please help!!

My hubby and I have been TTC for 6 months for baby #1 - I am a day late and earlier this month had unusual cramping and my breasts have been sore for over a week and only just stopped hurting the last couple of days.  I am still getting a BFN when testing and haven't had anything but a brown discharge for the last few days - does this mean I should just expect my period or could it be implantation?  I feel like I'm trying to convince myself I am pregnant as I have had so many symptoms this month - so would love some advice please!! Baby dust to all you lovely ladies xxxx