Flushed 2 days ago, why am I getting sick?

Yesterday, the day after my flush, I felt great. Today I woke up with my sinusis all stuffed up. I cant even breathe, not even a bit. This was the reason why I started cleansing in the first place at the end of January. My sinusis were fine once I started my master cleanse, but now I think this liver cleanse is somehow linked to my sudden sinus overflow.

Could it be that some of the toxins released are reabsorbed back into my body causing my allergies to do this? Or is this common that the immune system weakens for a couple of day after?