Could my cat be pregnant??

[MysticRose]

Hi, so we got a new cat she's 17 months old. Now I was told she's been vaccinated and spayed.
We took her the vets as she needed worming that was last week. The vet said to find out from the previous owners what vets she went to so they can trace when she was last vaccinated. So I did that and had no response from the last owners. (They were pretty quick at getting back to me before) week later and still can't get in contact with them. Now I'm wondering if she's even been spayed or vaccinated? The vaccinations I can get done anyway but the problem is that she's been going out. Last few days I've stopped letting her out now with being unsure. I've checked her nipples as I know that's first sign of pregnancy. They are slightly out and little pink. Just wondering if there's anyone who can tell if she is or if I'm being paranoid lol!
She's eating and drinking normal. She does have cat cold and glands are up so she been back vets today and had a dose of antis. She is very sleepy but I don't know if that could just be because she a bit poorly.
Tia

Could you not have asked the vet to check as they might know from examining her

Hi. I did she said she can't tell if she been spayed or not. She checked her belly and said she feels that she not had a litter before. TBH she wasn't really that helpful today. She just told me when they come into heat and that was it. If she is pregnant I think she would only be early on so maybe wouldn't be able to feel anything yet. I've had her 3 weeks now. X

I have no knowledge but she's beautiful!

Thank you x