Do you feel guilty when you kill insects?

Sometimes, I do. For instance, when I see ants crawling on the table, I feel guilty when I kill them. However, there is nothing else that I can do because if I just let it be, more will follow it after some time. Another instance is when I have to kill cockroaches. I absolutely hate them. They are dirty, and they are smell awful. Also, when they fly, I just run out of the room. Still, I feel guilty when I swat them. I always think that it's not their fault if they were made like that - awful, scary, and dirty. I sometimes wish that they will wiped off from the face of the Earth, but my grandmother always reminds me that every living creature has a purpose. Killing one will create ripples that will disrupt the balance of nature.