I'm also short (5'5"), but a decent-sized foot. I have an Ares Contrast, which has a very short tt of 17.8". I was running 175 length, but had the same issue as you do now. I found some 140mm arms, and wil be going back to them shortly. I can tell you now that you will feel VERY cramped with super-short arms. You may have to switch out your bars to adjust, or you just may hate it altogether.