Duffle bag too big?

I'm leaving for BMT next week and I'm rethinking my bag choice. I'm currently planning on a black duffle bag, but my issue is that I'm not sure if it's too big for a carryon on the plane. I know the guidelines are 22x14. Mine is 28x14, but it's all fabric, no hard parts and I've barely filled it 1/3 of the way full (to have room on the other end of basic) and I can fold it completely in half to be half the size, but is it still a problem?