Yo Lawyer,
Confidence has LITTLE bearing in this scenario. Regrets don't really come primarily from feelings of superiority OR inferiority. Regrets come from doing things that you feel might go against who you are AT YOUR CORE.
If whatever you do registers as being true to who you are on the inside, then the number of regrets you have for "doing" whatever it is you do will be minimized.
Often, we do things while on an ego trip or an emotional high that is not consistent with who we are as a person. So that when the "trip" ends, and the "high" comes down, we are forced to view our actions and decisions through the lens of our REAL perspective.
The only way to effectively combat this situation is to either change what you're doing, or change the way you THINK about what you're doing.
How is this done?
Well, any behavior we link enough pleasure and perceived benefit to, we are more likely to gravitate towards. And conversely, any behavior we link enough pain and perceived liability to, we are more likely to avoid.
And that's the best I can offer you, soldier.
March on.