when the water layer beecomes a semi-solid, you've got more NaOH than you needed. its hard to miss the phenomenae when it occurrs. though it may not have hurt anything, it certainly slows the migration of molecules upward, into the NP layer.
naturally, you could lower the ph with the addition of some water and some acid; like muriatic (HCl at 30%, more or less, in aqueous solution)
the result will bee the formation of NaCl, which can bee ditched later on, thru its unwillingness to disolve in alcohol; combined with the willingness of meth (and its precursors) to disolve in the alcohol.
i'm sure you'll figure out the rest...assuming this made a lick of sense.