Well my first question is when she went to the gynecologist did she go for this reason or just a routine check up on things?
If she went because you had unprotected oral her doctor would have tested for different things then a normal routine check up.
If you haven't told her which I suspect. The rawness that you are experiencing could defiantly be because of new or chafing undergarments.
Or could be early signs of Herpes, Syphilis, or Hpv.
although doesn't usually show symptoms right away could be the cause. Early symptoms, which are easily transmitted through mouth to penis contact, could show up as an irritation or strange dry skin then develop into painful sores later on.
Syphilis will normally show the same symptoms like rash or scabs on the infected area in the first stage then disappear for quiet some time even years before the second stage apears. Read ME Syphilis Symptoms
Hpv which is the least probable cause could show its ugly face in the near future after you develop warts.
Its really hard to tell without further information. What do you mean by sensitive don't be shy just tell it as it is just like when visiting your doctor were here to try to help.