Could that be mold?

Sorry Bro, but none of these pictures is really usabe to give you a good answer.. and btw the only "maybe" brown part i can see are the calyxes at the stem (which are sometimes finished earlier what causes also a loss of color)

From what i can see on the pictures i would say everything looks fine. Do you have a microscope? Magnified it looks like a fine web. In early stages its hard to see with the naked eye. There are super cheap microscopes that you can clamp onto your smartphone cam, not only handy for pest monitoring its also cool to take photos of your trichomes to determine the right harvest time. Make sure to clean with isoprop afterwords if you spotted the web

Unfortunately, yes, in pic three, right at the base of the flower in the background, it does look like botrytis/bud rot starting to form.

meh.. or just an overripe pre-flower... seems to be what you are focusing on is the preflower? those age a lot more compared to the buds since they form 1-2 weeks prior or even larger difference, if it's a photoperiod that grew preflowers in vege phase. I had some hollow out and taste like shit when i tried to wait for trichomes to be 'more' amber than usual. they turned a deep purple too, but genetics would vary on that. just a super over-ripe calyx. Had to take them off when i broke those buds up. if that is the focus of the pictures... wasn't 100% certain. Any discoloration should be a concern. it's not WPM in any of these pics, but other 'rot' would likely kill sugar leaves if it is lurking underneath. The blurry leaf with a little discoloration is curious - looks to be in 2 of the pictures 1 and 5. can't tell confidently from picture though.