Can you herx from Japanese Knotweed?

I've been on JK for almost three weeks. I started out slow and have only been taking 1 500mg capsule a day (Green Dragon).

Symptoms as of this morning:
-increased fatigue/weakness (can not stand up for too long without feeling need to sit)
-right sided tooth/jaw pain (previous jaw pain was on left side only)
-increased anxiety (nothing seems to help)
-head feels very heavy
-overall achy (not as bad as before but worrisome)

Wondering if it could be a herx from JK? There are a few people at work sick too, so it might be my body responding to those germs?

www.tiredoflyme.com/the-herxheimer-reaction.html