my 2 year old pregnant boxer

Question
Hello, my name is Heather and I have an approm. 2 year old boxer. We got our boxer (rookie) from these people that had to move out of state. Well here to find out they didn't take all the good of care of her. Well I told the woman we wanted to breed her possibly when she went into heat. She said that she has been in heat before and should be coming in soon. Well in July of this year she came into heat. Well, we bread her twice once one day and two days later we bread her again. She obviously took because we had her X-rayed and there was approm. 7 to 9 pups. I was wondering if we should go by the first time we bread her or the second time we bread her for her due date. I am stressing out because I am afraid she's going to give birth to these pups while we are at work and she's not going to know where to go. We have a whelping box for her and she knows where its at but my question is will she go there to have the pups? This is her first litter and my first time with a pregnant dog as well. She is our baby and want to make sure she gets through this ok. I am just concerned with the due date. I am thinking we bread her July 2nd and the 4th or 5th. I was kind of expecting her to have them around the 1st week of sept. And what happens if she goes past the first week of sept. with me knowing the dates we bread her? I would greatly appreciate some help!!! Thank you,
Heather

Answer
Hi Heather. Well, you have two due dates. You go by both dates. If she was bred on July 2nd, the she would be due on September 2nd. She would also be due on the 4th or 5th. If she goes past the first due date, then she may have taken on the second due date. If she doesn't go into labor by the second due date, get her to the vet for a check up. Don't let her go past day 65 of the second due date.  (Say she's due on the 4th, don't let her go past the 6th.) If she does go past this date, then she may need a section. Since it is her first time, I seriously doubt that she will know for sure where to have her pups. If you can, you need to have someone with her at all times starting the weekend before her due date. Boxers sometimes need help during whelping, so I strongly suggest having someone there. If I can help with anything else, let me know.