It could also be that you stirred up something, but it didn't get all the way out of your body during the flush and now it is coming out of your skin, or, you emptied just enough toxins out of your liver that your body decided it is strong enough to get rid of something nasty, perhaps stored in lymph tissues or other tissues in your head & neck region.
You might want to consider swallowing some activated charcoal or some colloidal water of Bentonite clay to help absorb toxins that are circulating.
You might even want to do another flush ASAP to help move it out.