On your conscience
Definition 1 of 1
Pro Tip 1/3Emotional Weight
Refers to the emotional burden felt when carrying guilt or responsibility for something. 
The thought of the homeless puppy stayed on his conscience all night.
Pro Tip 2/3Not Literal
It's a figurative term, not implying a physical weight on one's conscience, but an emotional one. 
She cheated on the test, and it's been on her conscience ever since.
Pro Tip 3/3Personal Responsibility
Used when someone feels personally responsible for an act, whether or not others know about it. 
Even though no one saw him break the window, it's been on his conscience.