obv this isn't an exact answer, we need more info and you could plug it into a DIN calculator, but i don't think it sounds like you're in the DIN range for 18s unless you crank the hell out of them. i'm a little bigger than you and very aggressive and i'm def not in the 18 range
it's been hard for me to ascertain over the years if it's a myth that you don't want to be at either extreme range of your binding's din range, but i've heard it from some very knowledgeable people including on here that yes it is a concern, and bindings are so important safety-wise that i'm inclined to act taking that as fact