Shakiness is definitely a huge part of anxiety, for me it's moreso my legs than my hands but I would say it's anxiety especially if it's coupled with other anxiety symptoms you normally experience. I would also say though if the shakiness is entirely random and you're not feeling anxious when it pops up I'd suspect something with the nerves. I'm no expert though

ex-band homie here (percussion gang)! Make sure to do wrist and hand stretches before practice to prevent repetitive stress injuries like tendonitis! anxiety can absolutely cause shakeyness, it did for me. If you start feeling pain in addition dont be afraid to go to the doctors, but if you warm up thoroughly (and i mean thoroughly) you should be fine, unless maybe its diff for colorgaurd bc its higher impact

i've done drumline for a while; it's a slightly different set of movements but i totally relate. constant strain on my hands, wrists, shoulders, and forearms have periodically eliminated my ability to just hold both of my hands still. made me freak out and exacerbated my anxiety at times. i don't think i would be too concerned unless it hurts or interferes with your ability to do day-to-day things. but, it also doesn't hurt to get it checked up if you're concerned about it. just remember to take it easy before and after you work on your repertoire, and always stretch! good luck on your guard endeavours ♡