Dark Brown discharge/ late period?

Sharna • I`m 24 and married with two beautiful boys ages 4 and 5 Expecting baby number 3 xxx
Hi yesterday when I did a pregnancy test it came up with a 1 dark pink line and one vvvfl also since yesterday I've been spotting when I wiped there was a little bit of blood on the tissue not enough to make a period though.. Also there's been very very  dark brown discharge in my pants since yesturday some times when I wiped it had stringy bits in it sorry for tmi, I've had some cramping in my pelvic area too and when I took a test today there was just 1 line in so confused I'm also 5 days late and on cycle day 35?   
I'm thinking a million things could I have ovulated very late and this is implantation bleed hence why the test isn't fully showing I don't no some one please give me advice.