You"ll be ok. I've finished crops that didn't look half as good as yours. Just go easy on your nutes until you can get a hold of the cal mag. Calcium and magnesium play a role in nutrient uptake and transport, so don't try to compensate, you"ll end up locking out your nutes. No fun haha been there a few times.
On your next grow, mix up about 20-30ml of cal mag per gallon, and let the coco soak in it, that should halt the mg deficiencies.
Just out of curiosity are you feeding every watering or flushing at all? I had a problem over nuting and over watering at first