Is my cat pragnant

Question
I have recently bring a new cat to my home. She's a 3 years old Chinchilla Persian and her previous owner was a breeder. I have brought her in not in the intention of breeding her and her previous owner has done using her to breed kittens and just want to get rid of her.
I have no intentions of breeding her and just wanted to keep her as a pet. However, a week after I got her, I need to go overseas and put her at a friend's house. They've got 2 male Chinchillas, one of them, later I found out has not been desexed yet(too young, only 7months old) and might have jumped my girl. When she first went over to their place she was at the end of her heat cycle. Still some callings but a lot fewer compare to the previous days.
I didn't think she was pragnant especially she just had a litter this year. Under normal circumstances even if I want to breed her I wouldn't pick this year.
The question is, is she pragnant. She was with the boys about 5 weeks ago for 2 weeks. When I first got her back, since she's still very new to me, she was not completely at ease so I can't tell if she's normal or not. Right now, she hasn't shown many signs of pragnancy. Or maybe I just don't know her enough to tell. I am not experience in this at all and the vet told me it's also too early to tell.
When can I find out if she's pragnant? If she's not I will want to spay her ASAP as I don't want her to go through another heat cycle. Quite a torture to her I must say.

Answer
You need to inspect her teats and see if they are pink or white. Brush her fur away and have a look.
If they are pink chances are she is pregnant. And pregnancy lasts 65 days from date of mating so you will have to work out when she is due from the date of the potential mating.
If they are not pink chances are she is not pregnant but this is not cut and dried. Give her another week and she if she comes into call. If she does she is not pregnant. By six weeks the vet should be able to carry out a scan and determine if there are any kittens inside her.
Good luck