You are simply suffering low carb flu. Some people do lose their hair with a sudden change to a carb restricted diet. It does not mean that your metabolism has plummeted or anything like that. Other sudden changes can also make you lose hair temporarily. 50-100g of carbs isn't so low that you will cause damage to yourself. Give yourself a little time to adjust. Things you can do:
- get more sodium, potassium and magnesium in your diet.
- eat an orange section or a sliver of apple if you are feeling weak or dizzy. Carry around a bag of slices so you can have one now and then.
Female, 5'3", 49, Starting weight: 163lbs. Current weight: 135 (more or less).
Starting squat: 45lbs. Highest squat: 167.5 x 2. Current Deadlift: 190 x 3