As many snakes as you have I'm really shocked you haven't been hissed at or bitten before. Some are all talk, I've got one, then you have some that will follow through. Then you have the bullys they bite first and ask later.

You might have scared her or she might have just had enough and was like Ok buddy thats it leave me alone.

The best thing to to is not get scared of getting bit. There are worse things in life. And remember that each snake has a personality and that may be part of hers.

Heck my Leo scares the little brown poo out of me when he hisses and lunges at me.

P.S most people that get bit say that they never saw it comming and the shock of getting bit was worse than the bit.