Firts Grow 4x +speed auto, CFL lights, DIY tent and Hot summer season.

Unless it's in an environment where more is present, it's unlikely WPM. It's more likely to be a dried drop of water from feeding or condensation. Wipe it off with peroxide and monitor it for signs of returning.

spray Neem Oil on plant it will help

I agree with numbers, less like WPM and more like mineral deposits. If it washes off your good. Good Luck!

I would 100% keep going with it unless you have a limit to hit and it would affect that. Just because it’s about a week behind doesn’t always mean it’s going to be any worse than the others. Sometimes it is true and will be a runt but more often they turn out to be just fine. My suggestion would be that if it is quite a noticeable difference in height compared to the others, prop it up into something to allow it to get the right light instead of staying in lower light. I hope this helps.

Unless you are limited by space or legal plant limits, there's really nothing to lose giving it a chance to grow. It's gonna produce way more if you let it finish than if you kill it off now. =)

Some of my delayed or mutated plants , despite beeing behind at start, ended up biggest producers. I would try to nurse, most will say don't waste time.....

Your plant needs some support to hold herself up. I do this by taking wire and making a circle at the top and bending the stake portion down 90 degrees. Put the stem into the loop and steak it down into the dirt so it supports it. The loop is great because it will support it no matter which way it leans. Also, give her more airflow once you steak it up. This will help strengthen the stalk. It will eventually grow up to where you do not need to steak it down. This is common with 1 week old plants. Hope this helps.

It either got a little leggy then top heavy or your light is too close. 4 inches does seem awful close. Honestly high wattage CFLs aren't your best grow light options out there. At a certain point the conversion from energy to light loses efficiency and produces more heat. You're really better off using several low watt CFLs than a single big one. LEDs are really the way to go anymore, best conversion efficiency out there.

Guess its because of the way it grew out. Maybe wasnt deep enough? If it would be sun it would turn the leaves away or more likely just burn itself, not bend its stem down. They arent that intelligent, those stupid plants :D You can put more soil, give the soil a slight pad( dont make it rockhard tho) and/or use something to stabilize, it will stand by itself in a week or so