I was at a nature site having a look around and hit my head on a rock - was a very upsetting moment!! Thanks for your comments, good luck with yours.
Thanks for the comment, I'm curious about scarring too, it probably looks worse in the picture than it actually was!
I posted a query on realself and had a very reassuring response from Dr William Rassman who seems to be a very reputable doctor and he said the following:
"You reported bleeding on your head 14 days after surgery fro trauma. I doubt that any significant damage is done if all of the crusts were off when the trauma occurred. I wrote a paper on this"
https://www.realself.com/question/united-kingdom-gb-i-hit-head-14-days-post-operation-bleeding-views-damage-pics#3624671