hi ...Thanks for your query
Labia and around are one of the most sensitive areas in human body.You may be having an allergic reaction
to the foam/ cream used while shaving or due to the shaving process itself.
You can start application of a mild steroid
in the area e.g. Hydrocortisone cream
once daily for about 5 days.Orally have anti-histaminic tab like Allegra
once daily to relieve the itch and discomfort.
Do not use soap /synthetic cleansers in the area .you can use medicated cleansers like Cetaphil
Sensitive skin cleanser to keep the area clean.Also apply medicated moisturizers like Cetaphil cream to prevent dryness.
Hope this is helpful.Take care!