http://www.yorkietalk.com/forums/1323848-post7.html
I'm not sure about the tums....I've never done that. My girl totally surprised me with her whelp a week before they were expected! The ice cream is a good idea in small doses, water if you can get her to take it (even if just licking if off your fingers). And the whelping pudding recipie in the attached link is great and Lexie REALLY liked it. I only used it after she finished whelping, but didn't know any better back then and wished I would have used it during also. Lexie I think got so tired during her whelp and her contractions stopped before the last pup was born. It was then that we took her to the e-vet for a shot of oxytocin.
From what you're describing, I'd say you will have pups tonight....but it could be a long night for you. Better put the coffee on. If it'd make you feel better, you could call the vet to let them know what's going on, but so far I think she's okay. Only if she is in hard labor for a long period of time with no pups would be when I would start to worry.
Hope this helps. Try not to worry so much and stay calm. Felicity can sense your emotions and if you worry, so will she (so to speak).