If the pantyliners are scente u might have a reaction
I've had that problem before. I was using cotton ones that irritated my lady parts and made me have a reaction. So I switched to the foam like ones and it went away.
This happened to me. It's just not so breathable. I watered down apple cider vinegar (2 tlbspn to a quart of water) and rinsed myself in the bath with it. Very soothing and it balances the ph of your vagina. I'm much better after that!
I delt with something similar come to find out its our soap that is causing my bottom and vag to itch like crazy so i used baby diaper rash cream and it went right away