Are you upset with where you are in life right now?
If not, then don't regret anything. Every single thing in your past got you to where you are.
If you are upset with where you are in life, Quit wasting time feeling sorry for yourself. The past is the past and there is nothing you can do to change it.
Look at your mistakes, Learn from them, And work towards a life you can be proud of.
Don't regret anything. Everything that has happened is why you are who you are. If you don't like who you are then make a change. Regret Nothing