Pics yet? Have to say things don't sound good. In a majority of cases it is not advised to be adding any nutrients during rooting especially if you are rooting in a potting medium. Additives designed specifically for the rooting process such as olivias cloning solution and clonex cloning solution are two great products that offer some nutitional value as well help in the rooting process. You may want to consider rooting cuttings in a ezclone or something similar, rockwool cubes or oasis cubes next time. Great/good airation plays an important role in fast rooting (4-7 days). The upper most growing tip/leaves (apical meristem) should in fact be the portion of the cuttings that look most healthy and leaves should be pointed up toward the light for sure by now. Yellowing of the bottom most leaves or what is left of them if you cut them in half is perfectly fine as long as all the rooting conditions such as, water quality, PPM, PH, humidity, temperature of the media/water and air, and light and its proper intensity and spectrum are all correct.