Running

Also quick question. I had my 5k run last night and this morning the arch of my left foot is really hurting, is this anything to be worried about?

Just to let you know I've got sports insoles in my right shoe to help with my IT band but I wouldn't have thought that would affect the left foot would it?

I'm guessing it could. I'm constantly running off injuries, and if one foot/leg is stiffer than the other, or better supported by bandages etc. The other one is forced to change the way it works, and/or do more work.

Also.
Arch pain is often experianced when you get new shoes. I'm not sure, but it might be down to the stiffer sole requiring more force to bend.