Cycle one--17 Day Diet for 7 Days--Reactive Hypoglycemia?

So, I have a part time job at a major retail store--trying to supplement my income through the holidays. I work 40 plus hours a week at my regular job and evenings and weekends on my feet at the retail job. I've been on the 17 Day Diet now for seven days. The first cycle is no carb (includes complex carb veggies and fruits) diet. I haven't been feeling really well--but I chalked that up to carb withdrawl. However, I found out yesterday (the hard way) that I can't do no carbs while expending calories. My research tells me that working retail (standing, walking for hours) expends about 250 calories per hour. Yesterday, I nearly passed out standing at the POS system waiting on customers.

The store wouldn't let me go back to work without being checked out by a doctor--so it was off to urgent care I went. The doctor asked a myriad of questions and we eventually came around to my diet. I told him what I had been doing and he asked me about how I had been feeling on the diet--so I told him: tired, a bit weak, headache, bouts of dizziness. I told him that I'd chalked it up to carb withdrawl. He disagreed. He diagnosed me with reactive hypoglycemia--I had no-carbed my body into insufficient glucagon production. Because I had completely done away with any whole grains, dairy (other than non-fat plain greek yogurt) and fruits and veggies with complex carbs for a sustained period of time, my body rebelled. He said that people really should not attempt a sustained diet of no complex carbs. He said that three days was the max time you should deprive yourself and suggested a sort of three days off carbs and three days on sort of diet (monitoring calories) if I want to lose weight. So last night, at my son's birthday dinner, I ate half of a Chili's Old Timer and about 7 fries. I felt better within a half an hour. Bizarre. Headache went away and I woke up this morning actually feeling as if I had slept. So, I'm starting anew--3 days on, 3 days off, while monitoring my caloric intake. We'll see what happens. Dropping 10% of my body weight in 17 days isn't worth feeling like crap.

Has anyone else had this sort of experience while eliminating carbs from your diet?