Carpenter ants develop wings and swarm in the spring and sometimes fall. I'd bet termites are the same. If one flew in the window, it's no big deal. They live in colonies and only have one queen.

Usually, there are signs of chewing and you see frass, which is sawdust-like waste.

I know more about carpeenter ants than termites, but figure out what they like (carpenter ants like damp wood) , where that usually is in houses in your area, what the signs are and check.

I agree with Sigrid. Termites do the same as ants and send out periodic bursts of winged individuals to start up new colonies.

This means you have ONE termite. :) But it's a good idea to do periodic inspections for more.