Could this be a sin, or at least poor morally?

So this might come off as a really silly question. But two days ago I had some flies that were really really annoying me so that I couldn’t sleep, so I put up a few glue traps around the house. They have been successfully catching a lot of flies now, but seeing them try to break free and thinking about how they will sit there and starve to death made me feel pretty bad for them. Like Isaac the Syrian teaches, a merciful heart extends to all living creatures. So could I be doing something spiritually wrong with causing these animals to die just because of their inconvenience?

Thank you for taking the time to answer this question even if it might seem silly