Delayed Blast Flatulence: 1 day/level seems a little excessive. Maybe reduce it to 24 hours or 4-6 hours/level? Unless you've got a good reason to let the spell linger for over 2 weeks before detonation...
Explosive Flatulence: One little discrepancy: the spell is listed with medium range, but the text limits it to just 60'. Other than that, it looks okay.
Flatulence: Very nasty! If it weren't for the fact that the target can still move, and try to move in your direction, especially if his allies guide him, I'd say it was overpowered. Since the target could bring the cloud back at you, I'd say it's strong for 4th, but still fits.
Food Poisoning: Considering how easy it is to just flat-out avoid poison, 6th level is probably a little high, especially since it doesn't do con damage. 5th would be fine.
Anger Deity: Much better. It's very nice, now.
Edit: D'ah! Can't believe i forgot about Food Poisoning! I added that now.