Dude, they look at trends.  If they saw that drop your last semester from 2 classes like psychology and basketweaving, they would think senioritis.  They might wonder about either your intelligence or your focus. (Part of that would also be looking at classes from before).
If they see it's from calculus and more calculus, it will make sense and no one will think less of you.
If it's from getting an F in freshman health 101, that would probably be a problem.
If your 4.0 was from your psychology major, and this term is your main brush with things of the difficulty of calculus, like this is your first term of physics and calculus, everything before was other premed prereqs like biology, I might wonder if you can only maintain a 4.0 in humanities and when hit with real science buckle.
If this was the only term at uni and the rest was CC, that would be different too.
If you've done all your premed prereqs with a 4.0 and this really is your last term ever and it's calc bringing you down, but still passing calc (I can never tell you a D or F isn't something to pucker over a bit) it wasn't worth anything anyone here has typed.  My fingers are annoyed at the neuroticism.