If the soil is sandy and well-drained, you may not have overwatered your peach tree. But if water stayed around the roots, you may have drowned the tree. For most soils, you need to water only once or twice per week. Less frequent, deep soakings are better than daily shallow sprinkles. The tree may also have been damaged in cold storage. If it was stored with ripening fruit, which gives off ethylene gas, stunting could result. At this point, make sure the soil is well-drained, water less frequently, and wait and see if the tree leafs out. Plants are pretty tough. You may be surprised by the growth the tree will make this year.