This question posed in BBC Focus has puzzled some people, and it seems that some animals behave according to their emotions, but ants have complex emotions like love, anger, or empathy, but they approach things they find pleasant or unpleasant avoided.
They can smell with their antennae, and so follow tracks, find food and to recognize their own colony. His exoskeleton has sensory hairs on the outside, but you probably can not feel the hurt inside, so pests can destroy them if they can get without touching the sensors.
Each ant brain is simple, contains about 250,000 neurons, compared to the billions that humans possess. However, an ant colony is as big as many mammals collective brain. Some have speculated that an entire colony could have feelings.