Chief,
I understand you lost a defense but weren’t granted a Shield? Please check the rules surrounding the Shield below:
- Town Hall destruction alone does not grant a Shield for the defender –At least 30% of destruction is necessary to get a Shield, and the attacker needs to deploy at least 1/3rd of his troops. A destruction percentage below 30% has a chance of rewarding you Village Guard.
- Attacking will eat away time from your Shield timer — it will not break the entire Shield, but instead deduct a time from it. You can see how much your Shield will reduce should you attack beneath the "Find a Match" button before battle.
To read up on the Shield and Village Guard, please have a look at the links below (English only):
http://clashofclans.wikia.com/wiki/Shields
http://clashofclans.wikia.com/wiki/Village_Guard
Clash on, Chief!