ACK! Not just weight loss, but hair loss, too!!

Hi! I would like some advice, please. I have had some considerable hair loss over the last six months. I have lost 81 lbs in 14 months. I started noticing the loss in the fall, after about 60 lbs of weight loss. I've noticed it at my hairline, and my hair just looks so much thinner than it ever has. According to MFP, my calorie goal is about 1680, but I frequently eat between 1800-1950 in total calories, 1400 to 1600 net calories. I exercise about 5 to 6 times a week (about 5 to 6 hours on average over the week). I used to do cardio 6 times a week - running, cycling and Zumba. I now do crossfit 3 times a week, sprints once a week, and running/zumba or cycling (but mostly running) twice a week. I aim for 120 grams or more of protein a day. When I first started noticing the hair thinning, I did some searching and I thought maybe my protein was low (and it was). But I'm still experiencing hair thinning. I did cut down on fat because I had gallbladder surgery last year. I handle fat better now that my body has adjusted to the surgery, so maybe I need to start focusing on getting more healthy fats now. Other than that, I don't know what to do. I did start taking GNC's Hair, Skin and Nails supplement. I was at my doctor's in December and the results from blood work was normal (annual physical). I'm about to go back because I'm really worried about this and I don't know what's going on. I feel like I'm eating plenty. In fact, my weight loss has slowed down over the last two months. Initially, when I changed up my routine to include crossfit, it helped me lose 10 more lbs but now I'm slowing down again. I feel like my body is fighting my weight loss now, and I don't know why. Again, I think I'm eating enough. I am making an effort to get more protein. I have 38 lbs more to lose to get to my goal weight. I'm worried I'm going to have to stop exercising and trying to lose more weight in order to not go bald!! Anyone have any experience or words of wisdom for me? Am I overlooking something?