Tightness HELP

So everytime something gets inserted into my vagina I end up getting tighter. Whether it’s fingers, my bf’s 🍆, or even a doctor vaginal exam. My bf used to be able to fit three fingers, yes with some trouble cuz hed have to force them because I’m naturally very tight, but now he has to force just to get one finger in. Is this bad? What’s happening to my body? Why do I get tighter each time instead of looser?