TMI pic! Not the best pic in the world

When I wiped with a little baby wipe and there was the tiniest and I mean tiniest little spot of what looked like brown blood. I got a positive opk on the 18th but I think it would have been positive on the 17th if I tested at night. 
​I had quite bad cramps on the 18th as well so I'm assuming I ovulated then too. This is what I could capture on my phone  
There's no way that could be implantation bleeding could it? I had a fair bit more with my son. Wishful thinking I'm guessing x