You can either live a life filled with regret or you can do your best to learn from the past, make ammends if that is possible while you are moving ahead.
^^^All these feelings are part of maturing. Welcome to the cusp of adulthood. (not meant to insult you or anyone that is reading this)
Life has a way of bringing you to your knees when you least expect it. Don't stay there long though, it's counterproductive.