My border terrier was mated 6 weeks ago. She was scanned at approx 30 days and vet could see no pups. Shes going for repeat scan this tuesday. She seems quieter  and very much more clingy than usual and her teats are definitely much bigger than normal. I cant tell for sure if she has white/opague discharge, as even when shes in season she keeps herself very clean. Sorry I know all these questions have been raised before, but Im really hoping that she is pregnant. I have read many time that larger breeds often dont show till late in pregnancy, does any one know about small dogs?? She has had previous phantom, so Im also concerned as to whether I should be increasing her food now or not!  Any advice welcome, thanks

I'm afraid it sounds unlikely she's pregnant, if there were no pups visible on the first scan. Wait and see what the scan reveals on Tuesday - a couple of days won't make any difference, and if she's missed then you certainly don't want to be increasing her food, or a rotten phantom is almost guaranteed. Until you know for sure, treat her as normal. Good luck.