Play or something else?

[Buttholelane]

Just finished walking my dog and we popped over to say hello to my in laws and their very noisy dogs.

Their two dogs were bouncing up and down barking and growling as usual.
The three dogs know each other and get along fine.

Then I realised it was actually my dog doing the growling!
There was no baring of teeth, I didn't really pay attention to her tail, ears etc but she seemed perfectly happy aside from really growling while pushing her nose through the gate slats.

Just a bit stumped really as to what to make of it?

She is quite a vocal dog and typically very growly when excited or playing but she's never really growled at another dog before.
She plays with these dogs frequently although has told one off before when it's been a bit ott.

When I got home I also noticed blood on her foot but can find no wound, was she behaving like that out of soreness..?

Growling can be indicative of pain so the paw could be the problem.

I wondered that but she made no noise when away from the dogs, I have been handling her feet trying to find an injury with no noise, and is resting on the sofa now.

Eric growls when he's excited So if I ask him "are you wanting things?" he jumps on my knee growling. Then I ask him "are you wanting walkies?" He jumps down, fetches his lead, and brings it back growling. He never shows his teeth in fact he usually picks up a toy on his way over and he's not at all threatening.
It's just one of his noises much like the yowling, snorting and sneezing he does to communicate.

My dog loki makes little growly noises when playing on his own and with me or other dogs it's just one of the ways he communicates. Some dogs are just more vocal than others.

Both my dogs growl, the eldest us very vocal and will growl, bark, howl and yap when playing (he sounds a nasty so and so but he isn't) the second one growls when she wants something!