Need help with snake not eating

[spartandude111]

My snake is refusing to eat. She is perfectly fine while the rat goes about it's business, until she gets too close or walks on her. Then my snake just hisses angrily. She will afterward just look up at me and wait for me to get her out of the feeding tub. She is like a teenage girl with an annoying six year old running around. I've had her for about a year and a half now, and she has never done anything like this before.