We have a cherry tree and every year it has produced pounds of cherries. This year, it produced a ton of cherries but they are about half the size of our normal cherries. The cherries are becoming deep red and have flavor. Any ideas what can cause this? How do I know if it is little cherry disease? There is also a fungus growing on one limb that was cut a few years ago but it has no cherries or leaves on it and it is the only area of the tree with it.