Help, could my little girl be pregnant?

Bit of a long story......
Little dog followed my son home five weeks ago, called the dog warden the next day who collected her...missed her so much and since her owners didn't come forward we decided to offer her a home with us.
Lovely little thing, very polite, well behaved, only barks when startled (four times in the four weeks we've had her)
Took her to the vet to have her vaccinated, vet estimated she's about four years old and has produced at least one litter of pups, he felt her tum and decided she was more than likely unspayed and to wait around a month before booking her in for the op, just in case she was due to come into season.
Ten days ago I picked her up and my arm became a bit damp, on closer inspection I noticed a very small amount of pink discharge and figured she must be coming into season, ten days later there is still a tiny amount, hardly noticable, it varies from pink to clear and I'm talking tiny amounts...probably wouldn't even notice it if you weren't looking...she also licks herself a lot.
She does seem a little larger down there (looks like a boy from behind lol) I put this down at first to the fact that she's had pups and then to the possibility that she's in season.
Out walking this afternoon me and OH were remarking on how much weight she's gained since she joined us, she was such a skinny little thing at first, actually we didn't notice how skinny until her fur was clipped (coat was in such a mess there was no option but to have it clipped right back)
She still very much has a waist but her ribcage looks wider...and then the panic set in!
I've had a good feel around and can't feel any bumps but from what I've read sometimes even vets can't tell, never mind a first time dog owner!
Could she be pregnant or am I adding two and two and coming up with one hundred?

Best person to advise you would be the vet - sounds as if she maybe in season at the minute - I wouldnt take her out or leave her unguarded in the garden. Male dogs can go to great lengths to get to a bitch in season

Make an appointment to see your vet + put your mind at rest

It sounds like she is having a season, though do go and take her to the vets They will be able to tell, and it will stop you worrying.

Well done for giving her a home too x x

Thanks so much.
Will book her in tomorrow, just voiced my concerns to DS and he says she doesn't look any different and I'm worrying about nothing.
Poor thing, new home and coming into season at the same time, how stressfull!
Another question, if she's in season now how long would I have to wait to get her spayed?

The vet will advise you, hon.

Hope all goes well, and well done for taking her in x

Seasons last 3 weeks normally.

Well done for giving her a home - when things have calmed down a bit - you must post pictures - she sounds lovely..

I think you are advised to wait three months after the end of a season before spaying. Good luck with her!

Most vets like if possible to spay half way between seasons.

Thanks for all the advice, took her to the vet and she was indeed in season...all over now!
So, looks like a 2/3 month wait til her op!

Just caught this....well done for homing her and glad it all worked out xxxxxxxx