While you are doing things in her tank, it's probably best to put in her a separate container instead of holding her. That would be less stressful.
Hopper mice are recommended for the first few meals, but given her size, that might be appropriate. CAN ANYONE ELSE CHIME IN?
Either way, you should be looking to move to a small mouse ASAP.
When you say, "work in progress" on temps, what's your timeframe?
Temp adjustments take hours. You have a snake that needs your help, please make this a priority.
She is probably underweight, being fed small prey, and doesn't have proper temps.
Again, not trying to be harsh, but she is depending on you.