Water damage. Please help me.

Hello there. 3 days ago, I found that the carpet right next to the ensuite bathroom was damp and wet. I did not use water for a while and checked the water meter. The water meter did not move. I think it means no water leaks. After showering, I checked the carpet and it seemed not getting wet. So I think waterproofing is ok. What I guess is... That night we had some rain. And the next day the rain stopped. When it rains the carpet gets wet(damp). When the rain stops, the carpet gets... Water damage. Please help me.
http://dlvr.it/Sj6679