Here are some ideas for you to check or try:

As one ages, even in dogs, they sometimes dislike anything around their neck. It seems that area becomes especially sensitive. You might try a harness instead of a collar and leash arrangement and see if that helps.

Have you discussed this with the vet or had her hips/pads/ spine checked out?

Is she constipated or otherwise in pain? Old dogs etc often have this problem and it's often overlooked until they're bound up tight.

She doesn't have to 'go for a walk' to get exercise...maybe she'd rather have some one on one playtime with you instead? Much more fun to chase a ball or play tug of war with you than to walk the same ol' walk every day.

When she pulls your arm/shoulder so it hurts, stop, rub your shoulder, and say Owwww! Don't do that, it hurts! She'll understand from your tone of voice and, perhaps this will help her 'ease up' a bit...unless she's angry at you for some reason. If she's normally friendly and obedient with you, she'll pick up on your pain also, if you share it with her.

My take on it is that she's telling you loudly and clearly that something is wrong...up to you to test things out and get her checked out to make sure it's nothing serious. BTW, check her toenails also. A torn or ingrown nail can be extremely painful.

Another thing to check for: a foxtail, especially if she has run on grass that may contain foxtails from rye grass. Those things can work their way in between the pads and embed themselves so all you can see is a little tail sticking out...very painful and must be removed, often by the vet. The stickers point backward so they're very difficult to just pull out intact.

Good luck being a dog detective.

Callie