The BSE benchmark Sensex today fell by over 14 points in the opening trade due to profit-booking at higher levels amid a weakening Asian trend.The 30-share index, which had gained 324 points in the last three session, fell by 14.60 points, or 0.07 per cent, to 18,740.85 in the first five minutes of trading. Similarly, the wide-based National Stock Exchange Nifty Index shed 7.20 points, or 0.12 per cent, to 5,690.50. In the Asian region, Japan's Nikkei was down by 0.44 per cent, while Hong Kong's Hang Seng index fell 0.39 per cent.