Is this typical behavior for a red-tailed boa? Are they generally this aggressive? If not, she might be grumpy 'cause she's not feeling well.

I bought my snake young, about as young as you aquired Dorothy, but Kelea never, ever showed aggression toward people; no hissing, no biting; just cuddling and liking scritches on the head.

This snakey-bitey thing is distressing!