thanks everyone, before I got your replies I went to my little local hospital and had him seen straight away. It turns out I am up for mummy of the year award
He has a sore bowel due to being given weetbix for breakky. No constipation or anything, just a sore belly from trying to process the high fibre content. so a diet change should have him good as new within a day or so.

Thanks for the replies! I just <3 this site and the ppl in it for thier help with everything