Hey firsttime, I would suggest you pluck a selection of leafs with trichs on from each plant, then put them under the microscope on a flat surface, and if possible have a look at the colour to know when to harvest (in the FAQ section, there is pictures to help).
If thats not working for you, maybe get a friend to help you out?

Either way, you're plants are looking tasty for bag seed, and happy toking.