Same boat for me too. Just coming back from an appendectomy in late Feb. Max distance was just over 13 miles.... Two weeks without any exercise and then the last two weeks slowly building up distance - 9 miles today, and the plan is the same tomorrow. It's kind of scuppered any chance I had of doing a good time, but finishing is my main goal now.
I was planning on tapering for three weeks with a 15 miler next weekend. The major problem I have is not knowing what pace I should set for the marathon. I tend to run at around 7-7.5 minute miles during training, so was thinking of going at around 8 minutes on the day and seeing how I felt.
Ken
PS Doctor said I was OK to run in case you're worrying.... It was a laparotomy, so not keyhole, hence the longer recovery time, but he thought eight weeks was enough time to recover and run 26 miles...