if it is a loose belt, I would worry about it as it will wear out quickly. The belts run accesories like your alternator, power steering, A/C, rad fan clutch. If you break one you could overheat or be stranded because your battery ran out of charge.
just push/pull on all the belts where they are not in contact with a pulley. if one is more loose than another, tighten it up!