If you're doing 20-25g of carbs a day, then you should go into ketosis in at most 4-5 days. Usually I can tell because I go from being depressed to elated. I aslo have a fruity, metallic taste in my mouth from the ketones. Buy some ketostix at a drugstore and check your urine for ketones, you may be eating more carbs than you think.
Suphedrine while chemically related to ephedrine is not the same thing. Get Xenadrine, HydroxyCut, or something of that type.
Some people can't deal with CKDs(I start going insane after about 4-5 weeks myself) and unless you're seriously overweight or are a bodybuilder more moderate approaches will probably work just fine for you. The Zone has also worked well for me and doesn't take much mental willpower, you just tend to be hungry. It's still easier for me to deal with than not being able to eat carbs.