Hi guys, today my 11inch macbook air was running out of battery, so 1 sec after it went to 0% and turned black I plugged the power in. when I hit a key, nothing happened. I hit the power button, and it beeped 3 times. and wouldn't stop!!! and wouldn't come back on either!! After that I forced-shut it down, and then restarted, and everything seems fine now. do i need to worry? what could that have been?