molasses is only really needed by the root zone and only when the plant cuts off sugar production to the root zone. This happens late in flower, like the last 2 weeks.
those are not balls. Most plants produce them, just weird calyx's that come out of stems for some reason. If you have gotten rid of the pest the plant should be fine,.
haappens to me sometimes when i trim/work on my plants. Marijuana plants irritate my skin and cause hives/iching, probably same as u, maybe wear gloves and long sleeves when working with ur plant?
many say OF lacks ca/mg but that looks like it could also be nitrogen, are u sure they are only 3 weeks old? id think OF would have enough to keep this from happening in 3 weeks.
i agree with olive it looks like N toxicity but that mix should be good, cant see it being that strong i use FFoF straight and never have issues how much botanicare grow are you feeding in PPM or EC?
Fix the humming, generally coming from the fan vibrating against something. I recommend you either suspend the fan from a couple straps or brace it with a piece of styrofoam insulation from home depot (1" foam should work)