Anytime you have concern about a program you are running, you can click "Pause" on a generator for a while to see if the issue correlates with the program. When things settle down, click again to resume.
Herx can come in many forms, so nothing would surprise me.
It isn't unprecedented. Individual bodies can do really funky stuff, and since I have one that is like the king of funk, I am really cautious when someone comes in with a wonky reaction.
Don't wait too long to try it again.
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