Peony flowered tulip mix

These tulips have been 'interesting'.  Bulbs planted late last October.  

The first ones to flower, which still show scraps of red petal at the front right and to the right of the bigger one, flowered at 4cm above the ground. The one in the thumbnail, and the yellow one, are about the size I'd expect, at 15cm or so. There are more in pots, some short, some at 15cm.  Not  clear whether the difference was inherent in the bulbs, or a side effect of lack of water - though all of these in the image are subject to the same irrigation regime.  Anyone else had bulbs which varied in their behaviour like this ?