They can make it a couple of weeks without eating... personally...I'd probably give him about 10 days. Did he have a rectal prolapse causing the bleeding? They did the xray, so unlikely to be a blockage then. Such a hard thing. Putting down a frog is not easy also, but better than prolonged suffering. I'd give him a good 10 more days though unless you notice a sudden change.

You could try contacting Dr. Frye and see if he has some input also - http://milanareaanimalhospital.com/aboutus.html - He is a great help.