I am too sensitive with noise!!

I wonder why this thing happened to me now. When i was studying, i do not have any problem with sleeping. I mean when I sleep, you can shout, you can talk, you can scream beside me and i can still sleep soundly. Sometimes i even need a backup alarm clock cos i can't hear the alarm when it's ringing.

I'm not sure since when i started to be very sensitive with noise. Neighbours open their door can wake me up, footsteps from the above unit can wake me up, even when you walk beside me without any noise i also can feel it. It's driving me crazy, why? The problem is after i woke up, i can't sleep anymore! I will be alert for at least 2-3 hours then only fall asleep again...

~sigh.. how how how? maybe i should try to cover my ears with something before i go to sleep, so that i can't hear any noise and can sleep soundly. But how to wake up? later canot hear the alarm clock ler..

Anyone having the same problem like me? How you deal with it? teach me teach me!!