Hello I am Dr Ravinder Sharma ENT surgeon
On the basis of information provided it appears that you had a streptococcal infection
in throat. It is known to causes renal involvement (caues inflammation of lining of glomerulus
- functional unit
of kidnney). It is difficult to find a reason for soreness of left breast but possibly the septic focus had spread via blood (hematogenous - via blood vessels) and is lodged in left breast. So theoretically it is possible.
There can be other reasons too. I would advise you oor a ENT consultation and a physician consultation to get the diagnosis.
I hope this answers your concerns. Feel free to contact me if your need more information on this
With warm regards