We all have moments we are indeed embarrassed of what we did and are much later 

still embarrassed of those moments. 

Our biggest mistakes are lessons but it can also inspire others too, remember we are with so many that it is impossible you are the only one who happened it too. By open up and by telling others about it ( on the internet for example ) or just keep it safe until the right time you know you can tell about it. 

Or it can be completely the opposite we can learn from the mistakes of others so we know how not to do some things. 

We are ashamed of our mistakes because of the daily mask we wear most of the time we sometimes want to be liked by others and we keep a lot hidden inside us. What can happen is the moment some people start to notice and rumors start to go around. It might 

be weird to say but it is a hidden way for people to find out what is going on even if they do it is a wrong way, we are alway curious about other people's life ( not all of us but a lot do ) and 

like to talk about it is not in a mean way but we like to spend time with tose who are the same or have the same way of thinking.  

In some way we are actually all teachers for each other we know at least one bad experience from someone we know wich helped us.  

We can also be critical about ourselves, wich can start on a young age on school when they only want an A just like the best of the class but they only get a B. It is like I said the beginning of the lower self-starts to talk. It can continue till adult hood. 

So the ashamed feeling and judging about who we are is also a lesson for others but  also for ourselves, it is just a circle wich needs to be opened otherwise the circle can continue.