Yeah, I think it was a combination of two things:
1. I think the initial irritation came from baseball practice, hitting grounders and fly balls to the boys with one hand. I really need to practice doing that 2-handed to protect my elbow.
2. This training cycle has certainly been hard on the forearms/elbows - snatching, pull-ups, probably hangboard too. So, just not a lot of rest after the initial irritation, accumulated fatigue eventually wears it down.
Next cycle I'm going to lay off snatches and pull-ups, give it a little break.