So the last two rows I've put in seem straight, but I'm getting a "V" between the boards along the width. Should I just take up the last few rows and reinstall them or is this a common thing?

The hardwood is 5" wide. I'm tapping them in before nailing them in with a floor nailer. There's no gaps lengthwise

Here are a few pictures to show what I mean.


I know its very small right now but I don't want to keep going if this is going to get more pronounced.

Wide boards are difficult to make perfect butt-joints along the wide ends of the boards as they are being milled. All you can do is tap the boards together, if they are in a straight row you will have better luck. There is a micro bevel around each board, so colored wood putty can be used to fill any gap, pressing it in carefully and wiping with a dry cloth.

Thank you, I will try the putty!