Chocolate Moose, I am marathon training but even though it was my longest run I'm not sure if it's a case of too much. The week before I did 21.5m too quickly for a LSR pace but it felt like a breeze. This one was only a half mile extra but it was really tough, at my normal slow long run pace - I think that was just tired legs though (maybe from the week before!), it has been a tiring month!! Taper is now beginning though, so I can rest a bit.
Helen Liz, I haven't had any temperature problems other than this, I run in the morning and other than being a bit tired and heavy legged I feel fine for the rest of the day. What you say about your problem with getting too cold though make sense to me though, I know if I have a temperature if I catch a bug I start to shiver and cool down really quickly. So it's hot water bottles for you and ice packs for me!
ATMF, maybe it is metabolism from the muscles repairing themselves, that sounds logical.
Thanks all of you for your help and advice. I think I'm a bit more comfortable that it's not something to get worried about now. A pain in the neck but not serious.
Thanksx