Has anyone ever seen a trauma mass on the back of their husky neck?

Notice yesterday a big lump on the back of my husky neck after playing with almost a year old German Shepard about same size. They like to bite each other neck but German Shepard likes to grab and pull. This is the first time she got a lump about size of half of baseball. It’s moveable and it drops to right side of her with her loose neck skin.  She is about 1.5years old and they played like this all the time before and never noticed anything like this. Maybe she had a small swollen neck after playtime I never noticed before?

I hope it’s not a serious one and it’s just a trauma mass from too rough play yesterday. 

She has no issue with eating or playing with little one and doesn’t feel any pain at all.

Out other husky is only 4mo old male. 

It could be from the playing but it'd be worth getting a vet check just incase

I agree with BB&S just to make sure