I have a 2 story house which is new (5 years now). The problem is when there is heavy rain and wind blowing on the upper and lower north windows (one above the other). Water is leaking from the first level ceiling and running down the inside of the window creating a significant puddle of water. I can see the water stains on the ceiling along the window. I assume there is a leak somewhere on the outside from the upper 2nd story window but can't find it. The windows have flashing on top and everything is caulked also. Are the drain holes plugged, which can cause the leak into the inside of the wall? Can water be going inside from the bottom of the window ? The 2nd story window has no leaks so it is not coming from the roof.