My 3 do this as well. They have since frog puberty i guess you'd call it. Moe, my silver(lucy too i think hes got kinda clear skin) is usually up once an afternoon, yells at everything, then re-positions and hits the snooze button. Larry, our honey bronze, gets up in the afternoon and eats, then snoozes, and shemp the big fatty, wakes up and moves when she notices Moe moved(they snuggle). When they're hungry, theyre all up during the day. When its due to storm Larry and Moe go nuts. Sometimes its just the froggy's pattern.
Others will be able to inform you better on health issues. We've never(thank goodness) had health issues due to out anal retentive care schedules lol. Hope i kinda helped.