1st Grow ever

Week 8 has passed and I ran into some trouble. The plants show clear signs of a deficiency. Nonetheless all ladies are covering their buds with glittering resin glands, as if they were slowly dressing up with jewelry for their last big show aka harvest day in a few weeks. I stopped feeding nitrogen in Week 7 according to schedule and the symptoms are not showing on every leaf but some the upper foliage. Yellowing, burnt tips and rusty spots. So I assume it must be a nitrogen and/or Cal-Mag issue. I started to add Bone & Muscle to the feeding schedule, as it's likely to address both with its combination of nitrogen, calcium and magnesium. Also dialed back the bloom channel of my growlight to about 70% to avoid further stress by light intensity. Day 1: 1 g / L Thycho Killer; 1 ml / L Jamaican Bloom Day 2: plain water Day 3: no watering as pots were still moist enough Day 4: 1 ml / L Jamaican Bloom, 1 ml / L Bone & Muscle Day 5: no watering as pots were still moist enough Day 6: 1 ml / L Jamaican Bloom, 1 ml / L Bone & Muscle Day 7: plain water