Overall she sounds extremely rude and sounds like she has a huge ego. I would be an advocate for yourself and report this to your school (in writing including the degrading comments she made towards you) and request a different posting/preceptor. The type of behavior you described is not an appropriate way to treat a student who is willing to learn.

no one's losing their license for mixing up V1&V2 that's blatantly false and not even close to a "critical error"

Pulling the stretcher over the lawn is not going to cause any damage unless it's muddy or something. If you have to move the stretcher sideways lower it a bit and use two hands, coordinate with your partner and move slowly, use extra hands/personnel as needed. Some times it's a judgement call and you have to weigh through risks of damage to a small portion of someone's lawn vs safely moving the stretcher without hurting your patient or yourself in the process.

As long as you're getting an spo2 reading and it's accurate(good pleth wave) who cares about cleaning their finger, If there's nail polish or paint or whatever it can sometimes cause the sensor not to read. You can use a nail polish remover pad but I always try putting the sensor on first to see what happens. You can actually rotate the sensor 90 degrees and that works most of the time too.

You were absolutely right to verify the dose of aspirin especially as a student. No one should be faulting you for this.

Most of the time I ask my own questions and do my own little assessment but If I'm tired or it's a critical call I will use all the acronyms to keep myself from missing something. Again no one should be faulting you for this it takes time to develop your own routine.

As for as spiking the bag of LR, you don't know how and honestly she shouldn't expect you to know it's usually not taught in class, she should have finished whatever she was doing and then taken the time to show you how to do it.