I've been pumping for 3 weeks and have quite the collection of flange sizes. 3 - 24m, 1 -27m, 1 -30m, 1 - 36m. I keep going up in size. It's annoying to spend so much money on flanges. I want to have multiple of the flanges I end up using that fit best but feel bad I've wasted so much money on flanges that don't fit. Is it common to buy so many to figure out the right fit?