My first time ... Windowsill grow

you can try pesticides or neem oil or whatever... if early enough yo may have a chance. google will have all the options on this for sure. Think you got leaf tunnelers too, or they are one of the ones you mentioned. I'm not a fan of spraying neem or other pesticides on something i will later burn and inhale. if it progresses, trash and do a very, very thorough cleaning of every nook and cranny. ensure no crumbs around the area to provide opportunities etc etc. if it doesn't die, try to power through it... then clean thoroughly. Get an enclosed space or some mesh that doesn't block too much light, etc. Otherwise, pests will be constant. Keep the sorrounding area immaculate too. no standing water etc. put out some sticky traps and other preventative measures. hope you live somewhere near the equator. a window sill may not provide much yield.

Hello.. Hope you are well.. Hydrogen peroxide will not only clean ur root zone but also give ur roots a boost of soluble oxygen.. This why ur plants have become lovely and fresh green on new growth.. It will effect places it can reach 1st more noticeably but ur central stem will cstch up with the rest and get healthy again.. Id personally leave it on and wait another wk for any improvement, if none the make the cut and remove bad/slow growth.. Stay safe n gud luck with her.. 👍🍀