Yeah... lights work... speedo runs up like usual when the bike starts normally. I do keep my high beams on all the time... that is the only thing "out of the ordinary". Everything is the exact same as when the bike worked... last week. Just clicks... a few flickers on the speedo... and it won't turn on.
so first its most likely the battery, when it was parked did you have the alarm on? if so then it most likely drained your battery down, and charging it back up, helped for a moment but that one start dropped it back down you didnt run the bike so you didnt charge it at all with that start, so im saying BATT is dead/on its last leg,
if the alarm is going on and off that to me is the battery having enough juice to start the alarm but then cutting out or low and making the alarm trip, so batt seems to be dying,
take it out and take it to autozone and have them load test it, be sure to say LOAD TEST, that will tell you if the battery is dead,
if you have a buddy who rides have him come over and put his batt in yours then start is and run it passed 5K rpms,
you can also get a voltmeter and check voltage before you start, then hit the button if its drops below 12 or 11 batt is done,
but from what you say I think the battery is gone, if it ran fine and you just left it chances are the alarm sucked it dry, check to see if the alarm has a cut off when the voltage in the battery gets to low, if not you will want to start the bike every week at the least and run it passed 5K to get a good charge from the system into the battery,