to feel alive

last night, for no apparent reason, i just didn't feel alive. i woke up this morning feeling more alive than ever. what accounts for this contrast? by 'feeling alive', i don't mean feeling happy or stimulated or even contented... it's something else... i'm just not quite sure what. it's almost a feeling of all the components of my being lining up with one another. my outsides matching my insides perhaps. but it's just so elusive, a mood that settles over us like weather. is this something to be accepted in an attempt to "be content whatever the circumstances" (Phil 4:11)? or it is one of those indicators for the soul that let us know that something needs to change (like pain to the body)?