It does indeed sound like a case of irritated hair follicles due to a history of shaving in the region.
What also supports the diagnosis is the fact that you do not have any other symptoms of an infection like frequent urination
, burning sensation while urinating, vaginal discharge
Please wear comfortable undergarments and apply warm compresses to region which will facilitate blood supply and time will surely make you feel better once the hair starts growing. In the future avoid frequent use of a razor blade to shave the region and try to use as much lubrication as possible to avoid irritating the hair follicles.
Hope this helps.