Help with dog behaviour- pain?

[Twinkle71]

My bitch is exhibiting strange behaviour when we come back from walks . She is a year old and very fit and active with no health issues. Whenever we come back she does this weird thing where she runs/scoots along really low to the ground and then curls up in a ball like she’s in pain, or launches herself into my lap and is really clingy.
I have noticed my other bitch doing this once before when her anal glands were impacted. She did the same thing with the slinking along the ground but She also cried and bit at them so it gave me a clue! But this younger bitch isn’t biting at herself , just looking really uncomfortable. It is always after a walk and lasts for several hours. I’ve checked her all over for anything irritating her but cannot find a single thing. She is due to be spayed soon so I’ll mention it to the vet but just wondered if anyone had experienced this before?

[PollyPolson]

I would as you suggest get her anal glands checked
I would also worm check her.
Where are you walking her? - could it be allergies to the surface or long grass

Assume you have checked her for ticks, fleas.

She is not coming into season?

I would speak to a vet asap to have her checked

The curling up into a ball is worrying.