Guilt is a crummy emotion, one that most of us try to avoid, either by not doing things we would be ashamed of (stealing lollies, cheating on our spouses) or by rationalising our actions so that guilt can be safely ignored (I needed a treat; my spouse is mean to me). But guilt is actually a useful, necessary feeling that helps us develop into fully formed humans with consciences.
There are plenty of situations where telling a lie can be beneficial, but it hardly matters if you suck at lying. If you want to be convincing, focus on eliminating the mental lag that makes your answers take longer.
Guilt can paralyse us if we don't know how to let go. A minor offence can haunt someone with self-inflicted guilt for days. If you want to get over it, ask yourself how a rational person would punish what you did.
