Something's not quite right

I have always been blessed with the ability to sense subtle things in life.
My best friend Susan calls it my "spidey sense". I can tell when things are just not right with people and animals even if they are not in my vicinity.
I awoke this morning with a feeling of something being not quite right.
At first I shrugged it off to the steriods I am on, they make me quite restless and anxious (just three days to go!). But when I went out to feed the boys this morning my feeling was right on. It was Tank, he usually drinks an entire bucket of heated water each night and I fill it up upon entering the barn each morning. Today barely a sip was missing! I tossed in his hay and grain and watched him closely. He is always the gentleman so my presence lingering over him got him curious as to the reason. I fiddled around the barn glancing over to see if he was eating.
All seemed ok so I went back to the house perplexed at the lack of drinking on his part. About an hour later I went out to turn them out for the day and most of the hay was still where I left it. Harley's hay was gone, gone, gone so I assumed it was not a mold problem. Just in case over to the hay pile I went , sniffing and sorting but all looked fine. I turned Tank out with his blanket on and he sauntered off as usual. I was a nervous nelly watching him all day and wondering was up. This evening I changed the water in his bucket and changed the hay in his stall. He seems to be eating and has no fever and good gut sounds so maybe he is just having an off day. The weather is doing a crazy dip and blow again so maybe that is it. Funny how well I know this horse after all these years and if I could bring him inside with me tonight to watch over him I would.
Instead I will be lugging out in the freezing rain and snow to check him a half dozen times tonite.