5 mile timed trial 44:00

Weight 215. Did 5 mile run in 44:00 (22:17 out, 21:43 back). Was hoping to hit closer to 43:00, but my pacing was off. Mile by mile breakdown was 8:59, 9:01, 8:28, 9:09, 8:23. My PR at this distance is 43:59, which I did sometime last month. Anyway, as I plug today's run into the race prediction formula, it puts me at a 4:15 marathon.