Does cephalexin 500mg...

Cause the external part of your vagina to burn when you touch it or itch? I am currently being treated for a uti and was prescribed this medication for 7 days. Day 3 I noticed this yellow discharge coming out, I was itchy and burned. Day 4 I used an  application of monistat which seemed to help the discharge. Instead of using the cream again I called my doctor and they prescribed me a pill for it. It is now day 5 and the itching and burning sensation is still prominent, should I be worried about this? Or is this a side effect of the medication? I'm just kinda nervous that this is something besides a yeast infection