: I'm not sure if my dog is pregnant. Please Help!!?

I adopted a female shih tzu and the lady I adopted her from failed to tell me that she mated with another shih tzu 2 weeks after I took her in. If in deed she was pregnant that would make her (60 days pregnant) today. She has been sleeping A LOT, but I'm just unsure because she has NOT gained any weight, but I just saw "pre milk" come out of her nipples. My question is, (Is it normal for her to leak from her nipples even if she wasn't pregnant?) And if she is why is she not gaining any weight? I would take her to the vet but It's really expensive and I don't have that kind of money. I would appreciate any answers, I just want to know what I'm in for. Thanks =/