Shingles is such a painful condition and it can affect your nerves, leave you worn out, run down and very unwell.  Have you asked if you can have the shingles injection to help you?  Obviously I can't comment on the pain under your arm as I'm not a doctor.  I'm sure it's not the end, I think you are run down,, worried and feel that you are not being helped.  But it's good that your tests came back clear.  I take a well woman vitamin every day, you can get them in any drug store, they take a number of weeks to feel any benefits but it's worth trying.  Eat well, get yourself less fatigued and hopefully you will feel more positive.  All my best wishes, Carol x