Hit by a truck (well dog really)

You might remember my friend Leslie, with the arm in a sling after surgery after she was knocked over by her dog at the park?? Well this morning she and a friend came to the park just as Bella and I were leaving so I could go to the gym (you know where this is going don't you?) and they had Arnie and Lucy, Leslie's two dogs with them.
I very nicely offered to pick up Arnies poop because Leslie was still in a sling and her friend looked freaked out by the thought- as was I but I figured if I can pick up Bella's, I can pick up Arnie's. As I walked back from the bin Arnie hit me from behind as he ran along chasing Bella and knocked my legs clean out from under me. The first thing that hit the ground was the back of my head.
It took me a little while to realise where I was and what had happened by which stage Leslie and her friend were trying to make me stay on the ground while I was trying to get up while the dogs were coming over to slobber on me.
I didn't make it to the gym and now I am sitting at work, my neck and shoulders are so stiff I can barely move them and I have a thumper of a head ache.
I think I might have to go home but I am moving offices to a new task force next Monday so I have a lot of stuff to tidy and arrange.
I haven't googled my symptoms (yet!) but I am tipping this could nearly be a mild concussion- all I want to do is sleep but Leslie was a nurse and said I should try to stay awake!

*Edit* I came home from work early and rang "Nurses On Call" and after asking a lot of questions the kind nurse stopped laughing at me and told me it was all right to have a sleep, some panadol, no alcohol and if my pupils were different sizes, my arms felt tingly or I started vomiting then I should go to hospital. So I have just had some sleep and I feel a bit better.