Memories

Is it possible that you start getting certain flashbacks and memories of things you actually don´t know that happened ? Like bad memories, that you hid somewhere deep into subconsciousness when you were little ... Is that real ?
And what is the cause, that triggers those memories ?
Is it bad to want to know more of what actually was happening ?
And if there were those bad memories, are there more that I don´t remember ?
More, that are going to show up and make my life even more complicated ?
I would really like to know the answers to those questions ... sadly I don´t ...