What is going on with my plants? Maybe overwatering?

Soil - water entire pot always.. never half water it, never chose to add X mL you chose whimsically. No dry pockets... Minimal runoff will ensure it got fully wet and not waste too many pre-amended nutes. Wait for top 1/2" to 1" to dry and repeat. Simple as that. How often you add fertilizer is a matter of how often you want to fertilize. More frequently = less concentrated. FFOF, if nothing was added, will likely feed the plants for 4-8 weeks. If you add perlite it'll be less nutes per volume and used up a bit faster, of course. You'll slowly want to supplement fertilizer it as it is exhausted. If not familiar with the products, maybe let it show first signs of deficiency, take soem notes, and pre-empt it next cycle. Easier to add nutes than to deal with a toxicity. If you see any droop, it is the fault of the substrate. Normal irrigation should not cause droop. If you see droop, that means you need to add more perlite or simialr to the soil before use. What a soil is mixed with in the bag is not always enough. With soil you want about 50% of volume to be perlite or similar. Coco coir only needs 33% because it holds 2/3rds the volume of water by comparison. Anyway, if it has a proper gas:water mixture in pot, it's impossible to overwater in any common sense context. If you water at same loss of weight, it'll require the same volume of water, so you can, in hindsight, learn the volume required in order to pre-mix anything or reduce waste etc. Following this SOP keeps roots growing downward instead of superficially. It maintains a healthier root zone haveing a wet-dry cycle. Keep it simple. Don't over think it. -------- confused, because your diary says coco coir... Coco coir or any other soilless medium-- 1) water with fertilizer everytime and get 10% running out the bottom. This water can be used outside but not for potted plants. Send it down the drain, otherwise. 2) Wait for top layer to start to change colors and repeat. Can't get any simply than that. Later on as you get into flower phase you can water more frequently and the developed root mass will make good use of it. You want at least a 1/3rd loss of weight before re-irrigating. concentration should about around 1.3-1.5EC (ferts only, tap water will add to that). It needs to be a well-balanced full diet at all tmes as a soilless medium contributes zero nutes. If this procedure causes any droops, it is the fault of how your substrate is constituted. Add more perlite next time, if so.