Could my female boxer be pregnant

Question
I have a 2 1/2 yr old female boxer, her 3rd heat. Since I don't know when she ovulates, I took her on day 7 & 9 of this heat, nothing happened. On day 11, she stood for him and they were tied for approximately 20 minutes. I took her back on day 12 but nothing happened. There was a lot of family commotion at the stud's house. Could that make her not stand for him or is it possible I missed my window of opportunity? Since they tied at least once, will she be definitely pregnant?

Answer
If there's a lot of commotion going on, it can interrupt breeding. Especially for the female, since she's at a different home anyway. If you bred her on day 11, and she stood and flagged, then she may very well be pregnant. Most people breed on days 11 and 13, or on days 12 and 14. Each dog is different though. There is no 'definite' in dog breeding, sorry to say. It can be so hard to predict when a dog ovulates, without doing progesterone testing and such. And even doing that doesn't guarantee anything. There's so much that can go wrong during a breeding, not to scare you, but it's the truth. I know people get frustrated with me when they ask, "is my dog pregnant?" and I answer that I don't know. I can't help it, no one can say for sure, unless they want to do a sonogram, or x-rays. She will convince you one minute she is, the next you're positive she isn't. Welcome to dog breeding. It will drive you crazy.:-) A good trick that I have learned along the way is this: if a dog's vulva stays slightly swollen after her heat cycle, and has been bred, then she most likely took. That's not 100%, but I have noticed that happening a lot with female dogs that had been bred. Good luck, and if I can be of anymore help, let me know!