Hello Fritz,
What you are experiencing is probably the Jarisch-Herxheimer reaction (also known as the die-off reaction), which happens quite often when people start to use MMS/CDS/CDL. The compound destroys all nasty germs inside your tissues, but cannot carry the corpses out of them. So all the toxins that were inside the germs start to float inside your brains, muscles, liver, etc...
So on the plus side, it shows the CDL is working, but on the minus side, the fact that you cannot increase the dosage shows that there must be a considerable amout of little critters inside of you.
So my first advice is to be patient, do not rush things, raise the dosage when you can, don't hésitate to lower it if you have to, but if possible try not to stop completely.
My second advice would be to help your body to get rid of those toxins. Most are eliminated through the liver, so herbs that drian it will help. Any cardiovascular effort can help but I found swimming most rewarding in case of brain fog.
Hope it will help you.