At 6 weeks, fiber may not be the best option for you only because you're still healing.
Better options to get things moving again: Miralax, Milk of Magnesia, Dulcolax, Smooth Move Tea. Depending on the severity of your problem, you can also try glycerin suppositories or even enemas.
Remember to be drinking enough water. The GI tract needs water to remove the wastes from your body.