don't know if I'm being paranoid on this but it's my second grow so I don't have much experience to draw on...noticed yesterday what seems to be a strange discolouration on the edges of 2 or 3 young leaves...my first thought was light burn since the affected leaves are at the top of the plant but none of the surrounding leaves at the top seem to be affected...my second thought was WPM but it doesn't look like white floury patches as described in GWE (plus air is circulating well)...she's in coco, watered yesterday, temps about 78-80° F., RH about 50%. the best way I could describe the spots is they kinda look like the "flocked" covering you see on air mattresses, etc. (not powdery). I also thought it might be just trichome coverage starting (3 weeks into autoflower) but I really don't know...any thoughts appreciated!