I'm gonna take a shot at this, although there are others on here who can answer it better.
1. Is your time of month (TOM) coming near?
2. Did you lose inches during this stall?
After you lose the content of some fat cells, those cells will fill with water. Be sure you are eating all your protein and drinking all your water. After a short time, those water-filled cells will be absorbed into the existing tissue, and the water will flush away. I know of people who have had stalls for around 14 days or more.
You might build tolerance to the HCG, but it's my understanding that won't happen until you are closer to the 6-week mark.
I don't know anything about Colonix or Toxinou; be sure you had read ingredients to be sure you aren't getting some form of sugar in them.
When you lose down to a weight you have stabilized at in the past, you will indeed hang there for awhile. Your body recognizes that weight as a set point of sorts, but you will eventually be able to push past that and continue to lose, if that's what you need to do.
You have had good losses so far; hang in there!
Karen