I got hooked on Star Trek
from the very beginning -- September 1966.
I was just about to turn thirteen.
We'd just purchased our first color TV set.
Now, that's what you call a perfect storm for making a kid into a lifelong Trek geek!
It was the original series when I was a child. It was an episode where Kirk and some others have space suits on and lies on a planet/ on the grounde and worms or bugs or something crawls into their ears and they cant take them away with their hands because´of the suits. This really got to me! It was very discomforting and horrifying for a kid! (anyone know what episode it was?)
That sounds like the feature film Star Trek II: The Wrath of Khan
. Maybe you've mixed it up with one of the original series episodes like "The Naked Time" or "The Tholian Web."