Is it abnormal that when I meet a man, I wonder if I’m only attracted/repulsed/neutral because of my species’ evolutionary need to spread the seed?

If I feel sexually attracted to a man, or emotionally attracted for that matter, I wonder if my biology will work with his… Maybe his pheromones lured me to him.. maybe he’s more likely than other men to get me knocked up, so to say.
I assume others have an off switch to this train of thought but I can never get this concept out of my head! It makes things very strange! When I get hit on, for example, I should wonder “normal” things like, “how much money does he make,” “what kind of car does he drive,” “how big is his man piece?” Instead, I wonder if he’s only hitting on my because I’m fertile… Would he hit on me at a different time of the month?
