How do you make repressed memories unrepressed?

How do you do it cause i've been having flash backs of before my best friend was shot in front of me when i was 6 even before my dad died when i was 4 1 & 1/2 weeks before my fith birthday. they are weird flash backs and i get them when i see pictures of me as a little kid, like my 3rd birthday i got to light the candles on my birthday cake (with mums help) or the pictures of me in the hospital when i was 3 and a quarter after i fell out of a window onto an awning, i remember the rush of air my mommy trying to grabb me the smell of the rubber from the tires on the cars on the street the screaming, my head hurting as i bounsed on the awning, then wakeing up in the hospital in a neck braise, the unfermillior white walls the doctor checking my vitals the sound of the people on the over com my mommy and daddy sitting next to me preying that i was okay my brother playing with his teddy bear, and the smell of the disinfected hospital, that's the reson i'm here cause when i smell that smell i feel scared, hurt, and like i'm unwanted or someones unpleased with me i don't know what that is but i have a blank time in my memories when i was about 5 & 1/2 i don't know what happend and when i bring it up my mum starts crying and saying you where so little and gone so long, and then she just hugs me, so how do i discover what happened to me when i was 5 & 1/2, please tell me and no stupid moronic or mean anwsers, please tell me i need to know.