The sudden intense pain a female experiences when observing a punch or otherwise painful stimuli to the male genital region
Vic: did you see that video of the San Francisco player that got his johnson grabbed in a tackle?
Cay: yeah, I had serious phantom dick pain from watching and I don't even have one of those things
A "paintbrush dick" is a semi-erect penis. Not hard enough to insert, instead bends like a paintbrush. I first heard it on Jim Norton's "Mouth Full of Shame" special.