Well seeds don't necessarily go "bad" but they can become unusable as time passes. It depends on what environment you keep them in.
Yes! If not stored properly or exposed to the wrong conditions, seeds go bad.
Caraway seeds
with a hammer
no
You can see images of both caraway seeds and cumin seeds by following the links below, although they do look very similar.
Shaajira
jeeru
Jeera
Caraway seeds
shahjiru
1 tbsp caraway seed weighs 6.7g
Kümmel
kala zeera