only scope trichomes on calyxes. ignore them elsewhere.
scope top, middle and lower levels. There will be differences in ripening. You have to make a guesstimate about that on your own.
While i don't think it is the case this time, it's good to recognize other physical observations you can use to choose a harvest date. Trichomes are the most correlative, but sometimes trichomes just don't amber up. I just let a plant over-ripen a bit due to that reason. In hindsight, wish i chopped it down about a week prior.
bud density and pistil coloration are good to pay attention to. When everything else looks good and trichomes seem stubborn despite waiting longer, it's probably ready. When it looks right there's usually 5-10 days beyond that and if you don't see amber starting, that's when i'd suggest to use different observations to choose harvest date.
being honest about this stuff can be difficult when first developing familiarity. the compulsion to chop outweighs rational thought. Don't worry.. being off a few days isn't earth-shattering.