Hi Rohan, try some Acidophlus, for a week, you just get them from your chemist, they put back your good bugs in your stomach, I would suggest you do a twice daily sea salt water wash warm, if it starts getting itchy dont worry its getting better, and if starts getting extra red again dont worry there doing that to get better its just blood forming to heal the healing.
Good Luck
I would think it was a yeast infection from taking antibiotics. You could take an oral probiotic and use Lotrimin cream as directed on the tube.