K-L-- the droops probably was a bit of overwatering,... this suffocates the roots, starving them temporarily for O2.... the guys here have you covered there! the tip burn, did that happen recently? Thing is, Big Bloom is not really a good fertilizer (I hate what they call it!), if you look at the N-P-K #'s you'll see that they are all in the decimal range-- beyond mild! It's good stuff, but I treat it like a supplement, and it certainly isn't good for a primary bloom fert',... Were you feeding Grow Big before?
Also,

soils have been very iffy lately, many bags showing to be badly off in pH, like low 5's-

... OF can be too hot for some too, causing such burns, even stunting, but your girl seems OK so far otherwise,... Tiger Bloom I'd start off at 1/4 strength a couple rounds first, just to see how she reacts, then ease it up if she does OK,...
Soil pH is everything, and knowing your water pH and ppm's, and your feeds pH will tell you if you need to adjust pH before feeding/watering,... managing your pH inputs goes a long way to preventing issues down the road! As a new grower, you'll need the right tools for this job.. do you have a pH meter? This is for liquids only... for actual in-pot pH, you'd best get an Accurate 8 soil pH probe, otherwise, you have to use the run-off method which is generally lousy for accuracy,... A TDS or EC meter isn't something you'll need everyday, but it's a vital tool for getting the right info about water and nute solutions,...