net current direction in a pn junction?
I'll just steal a diagram from the web so we know what we're talking about:



(Image source: circuitstoday.com)

In forward bias, holes are injected from the p-region to the n-region and then diffuse from left to right. That means current is flowing from left to right in the n-region.

Electrons are injected from the n-region to the p-region and diffuse from right to left. Since electrons have negative charge, this means conventional current is flowing from left to right, the same as it is in the n-region. 

In each region the injected minority carriers recombine with the much more numerous majority carriers. A tiny average drift of the majority carriers to "fill in" where a tiny fraction of them have recombined is enough to maintain a continuous current through the whole structure.