I feel like a Terrible mom...

I'm a first time mom and My son fell at almost 3weeks , he rolled off the couch YES rolled!! By himself , when he was being changed ,a big goose egg and a fussy baby later we took him to the hospital - FRACTURED skull and the brain has a slight bleed I feel horrible I couldnt get to him quick enough , or that we even took our eyes off him for a second to grab a diaper, such a horrible mom :(  Nurses have seen him roll so they know I'm not lying , but we will be in the hospital a few days for observation . My poor baby 😭