D&M, you make many good points. Your position is reasonable. But OP used the term upper teen, which I took to mean 17 or older, not 13 - 15, the "goofy" age. It is not the victim's obligation, IMO, to speculate as to this guy's intent. It was a dangerous trap, not an egging. And given OP's recent surgery, serious damage could have been inflicted. The law would have seen it as a serious matter, not a prank.
And I draw an enormous distinction between spraying and killing. We both have been gassed in our younger days and know it's a short lived discomfort. Pepper spray is similar. I've experienced that too in a training situation. I heartily endorse its use in this situation.
Anyone suggesting a gun be even shown in this situation is out of line and risking a life changing event.
But different strokes. I just see more need for consequences. You don't. That's fine.