Stem Rot?

Hi guys, bit of an issue (I think) with one of my wee ladies.

Growing 2 feminised Snow Whites in a closet with an NFT system under a 250W HPS light. Temps are around 23-27C and RH ranges from 40-50%. The plant in question is the plant closest to the pump and although I can't see any other issues with it, this morning I noticed a bit of a bother with its stem. The wee hunny is only 14 days from seed, is this stem rot she's suffering from?

Just a quick update on the progress of the oddity occuring with my stem to see if anyone can shed some light on it. Stem itself seems fine and strong, though almost as though it is peeling itself. If that makes sense.