Pregnant guinea pig near end of gestation period

Question
I bought two female guinea pigs from the pet store however, one turned out to be male. I noticed them mating one day (that's how i discovered one was male) and quickly removed the male. My female is now pregnant and has been for an estimated 66 days. She is very large and has been making weird squealing noises. It's not the same squeal she does when food is around. She did it all last night and partly today. I'm not sure if she's in pain or if it's normal for them to squeal so much before birthing, as I'm sure she has to be close.. I just want to be sure she is okay. So I guess my question is, is it normal for a heavily pregnant guinea pig to make weird squealing noises?

Answer
It sounds like she's going into labor. They do make strange squealing sounds when having labor pains. You may see her hunching up her back and pushing, and while she's pushing she will squeal. Not every pig does that, but not every woman cries out when pushing either.

Generally the gestation is about 70 days, but of course that's not an absolute. Once labor starts they usually pass the first baby within an hour. After that the babies come at about 20 min intervals, sometimes even less.  If she continues to do this and is not birthing she needs to be seen by your vet as she may have dystocia, a difficulty with the uterus or the inability to pass the babies. That's an emergency situation.

Hopefully by the time you read this you will have a litter of pups.  Please let me know what the outcome is.