First, I would verify the temps in the enclosures. A hot cage may cause agression. She is hungry, that too can cause agression. She has been shipped via USPS which means the content of the package was not known to the employees handling the box. They probably threw the box around, not knowing it held snakes, that too may cause agression.
So, what I'm saying is that your snake's past 2-3 weeks hasn't been a very pleasant experience.
I would feed it, and then leave it alone. Someone else said to cover the enclsoure, this is a good idea. Take away any and all stimulus.
Are you sure you are feeding the appropriate sized rodent to your snake? By feeding too small could cause your snake to always want more.
One question for you. If you remove the snake from it's enclosure, does the snake calm down? Maybe it's just a case of cage agressioin. Working with the snake over the next few months should take care of this problem.
Work with gloves if you are afraid of getting tagged. Welder's glove work well, but any heavy canvas glove will work.
Good Luck!
Jim Smith
PS Do you feed live or F/T? Maybe convert to F/T, this could decrease the agressiveness too.