small light leeks wont totally stop flowering but can slow down the process and even stress a plant enough to cause hermies, sit in your room when the lights are out and stay in there for 5-10 minutes until your eyes completely adjust to the darkness, you may be surprised what you find out...again small light leeks wont make a big difference, but if you can see things besides the little leeks like things in the room or your hand in front of your face, even if it's really dark that is to much light..you should be blind in there...