How long did you take Mebendazole? 1 day 100mg would be too short and low of a dose.
Normal treatment is 3 days in a row of 2xdaily 100mg, take it with a fatty meal and a tablespoon of olive oil, that way it remains in the liver longer.
You will need to repeat Mebendazole after 2 weeks, syptoms will return after 10 to 14 days, and to kill the freshly hatched eggs. After another 2 weeks its not completely recommended but I do it anyway I take one last tablet, just to be sure.
You will not find many worms in your stool they will digest, so don't be disappointed if you don't see anything.