not sure if this is the right board to post on but o well

Cassie my blue merle 2yr 8mnth border collie has just been for a walk through the ball for about 10 mins and then she was exhausted normally she does that for about half an hour and then wants to walk through the woods at the bottom of the field but today she just kept lying down panting and looked generally out of breath anyone got any ideas why she done it as it puzzled me.
she seems fine in herself

Have you noticed her coughing at all or anything? There's a lot of kennel cough about at the moment.

na she hasn't been coughing
she had her kennel cough jab done about 2mnths ago
her nose is cold and wet and she seems happy inb herself just doesn't want exercise unless she decided it was to cold or summit

The fact that she has had a kennel cough jab does not mean she will not get a different strain. But what ever the cause I would be concerned and think I would be taking her to the vets. Any sudden change from the norm should be cause for concern and unless you know why I would be inclined to look into it.

ill book her in at the vets for a check over just incase there is anything wrong ccoz it could be something more serious