Sounds to me like it's a fit problem with the new saddle (it's still new at 150 miles). Brooks saddles are higher than some others, so you might need to drop the seatpost a few mm. Likewise, if you're feeling uncomfortable pressure on the perineum, it might be time to rotate the nose down a few degrees. Yeah, I know, "everybody" says to tilt the nose up a bit on Brooks. But "everybody" isn't riding your bike, so adjust it to fit you, even if that means doing things differently.