Schaz, nerve is a funny thing. It might be that if you can just ride around on a lead for a few minutes you'll be fine but then again maybe not.
My sister was in a coma after a fall and took ages to recover, you would think that she would never ride again but she didn't remember the fall so she had no problems getting back on again even though she rode like a sack of potatoes for a while there (I hope she never reads that ). Other people have really gentle falls but that's it - they can never ride again.