I found a critter eating my plant

Hey,

Could anyone help me ID this pest please? I found it this morning, I spotted some tiny blemishes on one leaf of one of my three girls. I suspected nutrient burn at first as some of the tips are crispy, but I took a look through my loupe and this is what I saw... I'm in the UK btw

Have you checked more thoroughly I doubt one black thing that looks like baby pube could damage a plant