Your forg will usually find a single place to go back to and sleep. Since he/she is nocturnal, the activity is going to be when the lights are out.
You should see the glass smudged up some and if feeding from a bowl, then some crickets gone in the morning.

Keep in mind that a new frog needs to settle in so the less we disturb them the sooner they will settle in. My Red Eyed Leaf/Tree Frogs took weeks before I saw them move around at night and night lighting actually made them shy away from activity.