So a few days ago I heard a loud pop on my ride and after inspecting the bike I assumed that it was just a really unclean shift since I was going up hill. When I got home I noticed that I had in fact broken a spoke (it was still wedged in there and wasn't flopping around). I was getting ready to replace the spoke and I wiped down the rim and I've noticed small little stress marks going all the way around the rim perpendicular to the edges.
My question is at what point should I be concerned? Does this sound like it's unsafe to ride? I'll put up some pictures soon.