Help!!!! First time grow! plants dying!

HELPPPPP ME! im about a week away from harvesting my plants and they are suddenly dying! there has not been a single change to the grow room set-up and there are no bugs... the plants are not taking up water any more (its been 4 days since ive watered and my meter still reads as borderline between moist and wet). the leaves are all dying (some turning bright red to purple). two of the three plants leaves are just turning brown. ive been checking the trichomes and they arent quite ready to harvest... any suggestions

mine was the same the plants just using last of nute from leave so i believe
any pics and somone will tell u 4 shore

sounds like N defiency well not really the plant will feed on itself i had this happen before lost most of my leaves the buds were awsome