Loose terminals won't do anything.. thats ok, just won't charge the battery properly whilst driving.. which means you'll end up with a weak battery ot it won't start at all as it's not making contact..

Buying a battery charger is a must for everyone in case of stuff like this, $30.00 from supercheap auto dude will get you a half decent one.

it will take 30 mins for the alternator to charge the battery to a good cranking state (cranking the starter), but will take a little longer then that to get back up to full charge..

from memory most batteries don't receive charge till the motor is revving over 2,000 rpm