I was hoping to get a response back before answering but I don't want your girl to continue the way she is.
Stop the pro=pectalin. It is an antidiarrheal medication and a side effect of too much is constipation. Read more here:
So if she was having constipation already and you give it, she'll get even more constipated. So lets tackle the constipation issue after we are sure it is not an intestinal blockage. If she has eaten a non food item, bone, rawhide or pigs ear, then there may be the possibility she has an intestinal blockage. I don't think this is the case, but only you know if she may have ingested one of these items leading to a blockage. You normally will see a loss of appetite, vomiting, possible diarrhea and obdominal pain with an intestinal obstruction. It is an emergency situation. You can read about it here:
Now it is likely to be constipation as you suspect. If your dog is experiencing constipation on a regular basis you should add roughage to his diet such as canned pumpkin (not pie filling kind) or Metamucil. A spoon full of pumpkin on the dog's food should keep his bowels hydrated and his feces soft enough to pass. A one time use of a spoon of mineral oil on his food can also be used but should not be used all the time. This might be something you want to consider this time.
There are two methods I use for young puppies, which may work on your dog. I first try lubricating a rectal thermometer and take the puppies temperature. This frequently stimulates the puppy into going. If this fails and you have a nasal bulb syringe (aspirator), you can put warm water in it and gently squeeze a small amount into the rectum and see if this doesn't help as an enema. These methods tend to work on all dogs regardless of size.
You can use a children’s glycerin suppository depending on the size of your dog but the other methods are what I recommend you try first. For a tiny dog, I'd use an infant glycerin suppository.
I hope this information is helpful to you. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have . If you do find this helpful, please take this opportunity to rate my answer.