Hi thanks for your question.
The itching which your having inside your vagina colud be due to yeast infection.
The bump which your taking about could be bartholin cyst
are normally present in vagina and are important for lubrication of vagina.
They get enlaged when there is infection of gland or their duct get blocked.
You need to see a physician to get treatment for your vaginal infection
With treatment of vaginal infection , itching as well as bump will disappear.
Hope this answers your question.