change of pace; change of mood; (mental) break (e.g. going for a walk); refreshment
according to (depending on) the mood of the moment; as one's fancy dictates
festive mood; holiday mood; festive atmosphere
feeling great (refreshed)
happy mood; euphoric mood
the feeling between (new) lovers
complete change of mood; thoroughly refreshing one's spirits
disruptive mood dysregulation disorder; DMDD
dysthymia; persistent depressive disorder; PDD