A cycle?...please explain

I am ecstatic and suddenly feel that everything is falling into place.The past two months had been like hell and all things i cared about seemed to be moving away.Loneliness seemed to be the only emotion i was going through.But now,i feel a sudden surge of happiness,like a current shock pass through me.Instead of enjoyin this,i feel a weird feeling in the pit of my stomach,one that tells me that this euphoria is not permanent and that any moment,it would shatter.What goes round,comes around.So,i believe that everything is temporary.But,i'm thankful for the way i'm feeling right now as even a remote smile had seemed like a distant dream to me just a few months back :) So,is this a cycle? Only time will tell...