Positive faint line then a negative digital test. Help?!

My husband and I started trying again this past month and I have been going crazy with test taking. Last night I took a blue dye test and it seemed negative but after letting it sit overnight, it had a faint line this morning. It was clearly there. I got myself all excited and on my lunch break from work I went to get a new test to 'confirm' and chose the super sensitive digital, clear blue, and after an agonizing wait, it came up 'not pregnant'. I'm already past the date i thought I'd get my pregnant. Typically when it's time for my period I immediately have a lot of pain and super heavy flow. I've had a little spotting but it's off-color and it's not heavy at all. I think I had implantation just a day or two before I was supposed to start. Should I test again? Is it possible that it's still just too early? Or should I assume that this month is passing for me?