It is a big deal if it bothers you a great deal. The question is why. That's a question you need to answer. Does it come from a past sexual experience that's being triggered or maybe some porn that you saw? The guesses are numberous & if it brought you here, you're looking for some answers to make yourself feel better. There's nothing wrong with that mature type thinking.
I can relate to your post, except I didn't start asking important questions till I was over 35yo! Ugh.
Find your answers