It sounds as if you have some medical issues and should definitely consult your doctor before continuing with the cleanse. Have your read the book about this cleanse? It also sounds as if you are dehydrated. I, personally, would not cut out any of the recommended lemonades. You are going to lose weight as it is and need the nutrients found in the lemon and in the maple. If you are concerned about the sugar, try cutting down on the maple a little. You are using too much cayenne as prescribed by the book. It does say, "add cayenne to taste", but you are using a lot. Cayenne can produce an allergic reaction making your eyes and throat burn and make it difficult to breathe. Just don't overdo it.
As far as your nasal breathing is concerned, have you ever done a nasal saltwater irrigation otherwise known as a Jala Neti? I had difficulty breathing until I used the Neti Pot. I am not soliciting as you can buy neti pots at almost any drugstore, but I have some listed on ebay. I am finding that using the Jala Neti is a wonderful addition to the cleanse. I am on day 7.