Young dog seems excessively unfit

[petitdonkey]

Hi all,

My gorgeous dog is 18months old - he is a miniature Labradoodle so about the size of a small lab/ springer. My concern is that he gets so out of breath and recovery time from an energetic walk seems to take too long.

When we went to the Vet for his 12month boosters he said that he was the top weight he should be so I have upped his exercise and am careful with his food.
I have also started taking the ball wanger on walks so that he gets a good run. We have just got back from a 40 min walk where I began throwing the ball (all of our walks are through fields) but after about 10 minutes he was panting so much. We just walked for a bit but he is desperate for the ball so I threw it again for a while. He then was panting excessively and stopped for water at a sheep's trough which he attempted to climb into. He then lay down twice. We got home and he lay under the bushes waiting for the gates to open and looked like he would happily stay there. We have been home for fifteen minutes and he is still panting. I also think that when he walks he looks a bit waddley if that makes any sense.

Should I take him to the vet? I think I should but don't want to be PFB!

[Turniphead1]

Labradonkeys I have heard them called. Bigger than either of the parents.