I suspect you should do some more reading about chains. Your knowledge base sounds very small.

Add lubrication. If it rattles when you tap it that means the rollers are moving freely, not a bad thing, usually just a sign of being under-lubed. You can't really damage a chain the way you described. Worst case scenario is you reduced the life by increasing the wear on the pins due to more aggressive friction during rotation, this causes the grit in the chain to wear into the pins faster but it will reduce the lifespan by single percentage points and will not cause excess noise.

What do 12 links measure out to? 12 1/16" is worn, 12 1/8" is time to replace.