Why do you think my Meyer Lemon is dropping fruit?

I have one that I overwintered in a pot in the house. Most of the winter I had it in a west facing window and it produced one good lemon. It was blooming again and I moved it to another location it just didn't like and it dropped all its flowers. I live in central Alabama and moved it outside in April on my patio which is exposed to mostly the west but a lot of sun from 11:00 on. I have it on a watering timer with several other plants, bulb beds, etc. I water everything every day for about 20 minutes now that we are 95 degrees plus every day. In April the tree was doing fine, had abut 6 fruits set on and started to bloom again. Then, all of a sudden all but two lemons died turning yellow then black. All the blooms have ddisappearedand I have only two lemons left. I am wondering if the hot spell is getting them, although the foliage looks all right or maybe I watered too much. I took the mister out of it and am thinking about moving it more into the shade too. I fertilized it last fall with a blend of organic fertilizers that should now be broken down and usable Any ideas, too much water, too much sun, too little fertilizer?