Nevro charger problems

I recently had a Nevro HF10 stimulator implanted and I’m surprised by the lack of tech support available. There’s a lot of sales information but not much in terms of FAQs. Is anyone else in the same situation as I am? I have some newbie questions:

  1. If I forget to charge the stimulator for a few days and feel worse, does one blinking bar on the remote mean it’s dead or just low?
  2. Does the effectiveness of the stimulator decrease when the battery is low?
  3. I’ve noticed some heat from the implant when the battery was low. Is that normal? Any tips would be appreciated!