Pregnancy question/advice

My dog went into heat sometime early December and around 12/17/16 my sisters dog (male) escaped from his kennel while we were gone and we aren't 100% sure if they mated while we were gone or if it was during a different time when we weren't paying enough attention to keep them separated. But fast forward to now, my dog (she's a Pekingese) is 7, so naturally I was really worried and on 2/18/17 we brought her in to confirm our suspicions on if she was pregnant or not by getting an ultrasound and it turns out our suspicions were right, we were also going to get an X-ray to see how many puppies there were and if this delivery would go smoothly but their X-ray Machine was down (before anyone gets mad this was 100% accidental, the last thing I wanted was for her to get pregnant this late in age and we were going to get her fixed after she stopped being in heat). Over the course of the week she's shown signs of starting to go into labor, on 2/17 her temp dropped to 98.3 and she started having clear discharge. from what my vet said she was supposed to start to have her puppies Within 48 hours because of the temp drop, but I heard that the temp drop isn't always a for sure sign of labor or it can also be a "false temp drop?" Since the vet appointment her temp has stayed below 100 and has gone anywhere from 98.3-99.9. She lost her mucus plug I believe on either 2/18 or 2/19, and the last two nights she would be up at night panting, nesting, and either pacing or walking around in circles, when she wasn't pacing or something she'd be sleeping, and her stomach would tense up so I'm guessing she's having braxton hicks? id be rubbing her stomach and she'd be laying on her back sleeping, then next thing I'd know she'd start growing and wouldn't let me rub her stomach anymore, then she'd roll over so she'd be laying on her stomach, and after awhile she'd roll back onto her back so I could rub her stomach again, but she still hasn't giving birth to any puppies, and her water hasn't broken? yesterday all of her puppies were moving down towards the birth canal and being really active with kicking and moving, the kicking has calmed down so far today. What are your guys' thoughts? Should she be going into hard labor soon? We called a emergency vet because I was concerned but they said that I shouldn't be worried unless she's pushing for 2 hours with no puppies coming out. I just wanted to know what your guys' thoughts on this were? Thank you