hair loss

For the past 3 weeks i have been loosing more hair then usual. I'm starting to really freak out. I have lost about half of my hair now I talked to my nutritionist twice about this topic before surgery and believe it or not i got two different answers. 1 answer was i will go through one major cycle of hair loss but it will grow back and she said there was no magical vitamin i could take to stop it. Story # 2 was the week of surgery she asked if i had anything that concerned me i told her hair loss and she said you wont have any hair loss due to the fact that your weight loss will be slow. I looked at her like she was crazy and told her what she told me the first time we spoke and she told my i must have spoken to one of her interns that she would never say that. (she was what i like to call crazy town) with all that being said what should i do. I take my daily vitamins, i make sure i get my protein in. Has this happen to any one else.