Triple 2x4 beam post bowing away from foundation wall
That's possibly just humidity warpage and not due to load stress. That nail wasn't intended as a structural component. It probably just held the post up until there was something on it. At any rate, no, you don't need to jack up the beam. That amount of bend results in approximately 0.0" of settling in the beam. 

I'd watch it and see if it moves any more. If you're worried, run some concrete anchors in. The problem is that you can't drill for typical expansion anchors since the lumber is in the way. You'll need to use something with concrete-ready threads. 

Another option would be a steel U-strap bolted directly to the concrete.