Often, my hands lightly shake and I don't feel good. Could it be an anxiety/panic attack or something else? I haven't been diagnosed anxiety.

See doctor. You're 16 and likely healthy. But first get checked by your pcp to make sure there is no medical reason for your hands shaking often and "not feeling good." Write down when this started, any triggers, what helps, any medications prescribed or OTC you take, any alcohol or drug use, caffeine intake, cigarette smoking and review with your doctor. Ask if anxiety could be the cause. Hope this helps.