Over protective mom

I have one female alpaca who has been more challenging for me than my others. You can tell by looking at her eyes that she is oh so frightened of two-leggers. Four-leggers make her nervous too.

She is 7 years old and was not halter/lead trained when I purchased her. It was definitely a challenge for me to halter train her, but I am working on it and making progress. She had a cria this week and is, for the lack of better words, over protective of that cria when it comes time for me to do necessary care, take temp, shot, etc. When I say over protective, I mean she bites me on my arms (through layers of clothing) and scalp - hard, breaking the skin and leaving bruises and abrasions. Unfortunately, I am just the perfect heighth for her to bite my scalp.

My husband now insists when it is necessary for me to care for her cria that I wear a hockey helmet. With much reluctance on my part, I did so last night. She tried to bite the hockey helmet, I had no abrasions on my head.

As in most cases, probably all cases, I am sure there is something I am doing that is wrong, or something that I am not doing that would be right.

Please help.