Dog pregnant?

Question
I have an english bulldog. I have a feeling that she is pregnant. She has gained a lot of weight recently(also, her nipples have gotten larger and her stomach itself has begun to swell).

How can I determine if she is pregnant? I know that I need to bring her to the vet, but how much do vet bills average to determine if your dog is "truly" pregnant. I don't want to go and spend a FORTUNE at the vet if I could easily determine myself if she is HONESTLY pregnant. HELP ME PLEASE!!!

Answer
A vet visit can range from $35 to $50 for an evaluation.  There is a blood test to see if your dog is pregnant that may be $50. If she is far enough along, the vt may X-ray the belly to see.  THat may cost $75-$100.  Do you know if your dog got bred?  She may be experiencing a false pregnancy.