Okay I am ready; I am posting my answer here;
You have mentioned the pain appear to be deeper than just on the surface
There could be certain infectious processes (like developing an abscess) in the back can cause these type of symptoms
Certain other inflammatory processes of the back too can do this
Rarely even a disc problem in the spine too can cause these symptoms
This needs to be examined by a DR asap, also you need certain relevant investigations like an MRI scan of the back/spine etc which will help in clinching the precise diagnosis and then treated appropriately, depending upon the test results
In the meantime for the symptomatic relief you may try one or more of the following;
Calmoseptine over the counter skin ointment can help in relieving this severe annoying prickly pain
Another over the counter option is Calamine skin Ointment or Lotion
A nerve-pain pill like Gabapentin or Amitriptyline can also of immense help with this type of annoying prickly pain
And as discussed earlier above please try to get this examined & evaluated by a Dr asap, if early clinic appointment is not available, then visiting ER or Urgent care is recommended.
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