If other people ate the same food out of the same dish at the same time as you and didn’t get sick, then it is less likely that you got sick from the food. It is still possible, though. Some people may be less susceptible than others. Timing is also very important. If you finished off the guacamole at the end of a party and everyone else ate it at the beginning of the party, then you might be the only one who got sick. Please seek medical help if you get too sick.