Sounds like you weren't getting enough calories--hair loss so soon after is a big clue. Not getting enough calories mean you weren't getting enough nutrients which mean not enough electrolytes (Calcium, Magnesium, Phosphorus, Potassium, & Sodium) and being deficient in any one of those can cause heart palpitations:
Freelee & Durianrider recommend at least 2,500 calories per day for women on this diet (3,000 a day for men) and if you exercised a lot or had a lot of other forms of stress good or bad, you would have needed at least between the 3K-4K range.