This could mean almost anything. You could have an energy blockage with the lungs system--which includes the breathing of the skin. The energy being released from old blockages could feel like bugs (I've had it happen). It could be an energy block behind your head that, as it dissolved, felt like an insect flying away...
It could also be something abstract that your Soul wants to show you---one time my sub-conscious said to me "if you see ants, offer them sugar" a few moments later the entire room and myself completely vanished and was replaced by a massive flow of cartoon (animated) ants that left as quickly as they came. I'm not sure what that was about but it was pretty cool.
There are many reasons these types of "bizarre" events unfold around us. It's our Spirit telling us something. You might be sub-consciously afraid of insects, and that fear was brought up for you to diffuse it...and your ego mind tricked you into thinking you are just now being afraid of it. (an old energy presented in a new package--which is something the ego mind does) Another way to explain it is you were once so deathly afraid of insects that you suppressed that fear and your Higher Self helped you slowly diffuse it. (something the Higher mind does for a lot of things, like an inverse of the ego-mind's view of it)
There is some reason this has come up for you. You might even be feeling the life-force of the insects themselves. Don't be afraid of that. In fact, insects are a trillion times more afraid of us than we are of them. It took me a long time to understand this myself.
When I was young I saw a group of caterpillars huddled together on a tree. I saw this and it freaked me out for a long time. I couldn't understand the "weird scare feeling" I got from just looking at them... Years later, I realized that the insects huddled together because they were afraid...and it was really me sensing their fear. Not the other way around.
Separation in the energy world is an illusion are you are ONE with the energy labeled as 'insects' and their associated feelings, whether or not they are real or abstract.
Whenever this comes up, don't worry so much about it. And if you can't get it out of your mind, then use it as an object of your meditation. Look at the energy of fear you sense when you think of it. As soon as it becomes an object of your meditation, notice how the fear dramatically decreases......
I hope this helps,
~Z