Ah thank you for replying
I do get the pain at other times, sometimes it's just a stabbing pain when I'm not even moving, and it used to hurt on ocassion whilst just walking, so much so that I would double over in pain.
The doctors mentioned IBS, however didn't sound very convincing and haven't helped alleviate anything in all this time, hence why I joined the forum. I shall try experimenting, I don't eat dairy as it is, therefore I don't think that's the problem.
I do often feel very stressed before running actually, I'm not sure why, it's just the thought of it I think, so will try relax more now, and I'm sorry you've had to suffer too!
Thank you so much for your help and comments 