don't you have to get the hips x-rayed to see if your dog has HD.
For working dogs, if they have it, x-rays are usually moot. In other words, you usually can tell after they've been worked hard.
7 months old is a little young to see HD. It's usually seen in large breed dogs. Check her over real good, could've been she injured herself somehow on the hunt. Give her a little time and see if it gets better. If the problem continues, it's a definite possibility.