Cat hiding after being stepped on

That's the typical behavior of a cat who is in pain..... I would take him to the vet if he isn't better by now. Please make sure he eats well, also - this is very important.
Cats are amazing at hiding pain - so they will do their best to no limp, walk normally, etc, to the best of their capacity..... That is a defense mechanism they use in the wild for safety but hiding and behavior changes are tell tale of that.
If your cat starts hiding, especially if that hiding affects meals, you can bet there is something wrong - with my cats it is a sure sign that they are not well. IMHO a vet visit is in order for sure

P.S.: If your vet wants to give an injection of Metacam (Meloxicam) for pain, refuse it - get another anti-inflammatory or pain medicine - it is prescribed very often, but can be very dangerous as well (risks of kidney failure and death) - not FDA approved for more than one use per lifetime for injection (for bone surgery and spays), and never oral.

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First of all, I hope you are not beating yourselves up on this. Both DH and I have accidentally stepped on our cats over the years and sometimes it just happens. Some cats just make great speed bumps that can't be avoided.

I've seen cats respond in very different ways to this situation. Even if he wasn't hurt when your DH stepped on him, he was very scared by it, and most likely lost some trust in his "humans". Most cats will run off and hide for a bit when things like this happen, and their personality and how you respond when the incident occurred can influence how long they hide. I have some that will not hide at all (they prefer to dramatically flaunt in my face that I did something wrong to them), and others that go immediately under a bed. My concern would be if they are not coming out for food/water and to use the litter box. That tells me they are trying to hide their pain.

To regain his trust, go into the room where Floyd is hiding and sit down on the floor with a good book or magazine and start reading aloud to him. Don't force yourself on him, but allow him to come out and snuggle up next to you. If he likes treats, bring a bag of treats with you and crinkle the bag so he hears it. If he comes out on his terms, he is losing any fear he may have of you right now. Doing this will also make him more relaxed, so that if he is in pain, he won't try so hard to hide it from you. You can make a better judgement on whether he is simply afraid or in actual pain.

One of the things I've learned to do with mine is that if something like this happens, I immediately apologize to them, tell them I love them, and give them major "please forgive me" scritches all over their bodies, followed by some treats so that they forget what I just did to them. The key is to get them distracted by the incident as quickly as possible so they get over any ill feelings they have towards you immediately. I'm sometimes surprised at how well this works.

I agree with Momofmany, don't beat yourself up over it.  Floyd is just being a baby.  He is not hurt.  Cats have a high tolerance for pain especially their feet.  If any thing is hurt, it is his pride.  And, that will heal soon enough.  I would give him time to get over it and let him come to me.  But, if you really are worried, just lure him out with treats or meat or something you know he can't resist.  Pet him and apologize to your hearts content.  You'll be back in his good graces very quickly.   

Well.... This is it..... If you read the OP's post - the cat is not coming out for 2 days for meals... This is my concern right there - it is not the hiding from humans
That's why I posted that he must be in pain. There is a clear difference, to me, in between running from me when I come into the room, but resuming all the activities when I am not present.... and hiding even from food.... Whenever the later has happened here in my house, there was always something wrong. It was never just a fear, or psychological trauma - it was always pain. At least this has been my experience

I doubt there's a cat owner alive who hasn't accidentally trodden on a paw or tail or two in their time. These things do happen, especially if you have a cat like mine who runs into our legs like he's trying to trip us up! Don't beat yourself up about it. However, the fact that he's not coming out for meals and it's been over two days now concerns me too. It seems an excessive reaction if he's not actually injured. I would have him checked out by the vet just to be on the safe side.

I remember stepping on Monet's tail long ago. He didn't even move, but meowed over and over until I realized I was on his tail. It was like he was saying "Excuse me, please get off my tail. You can get off my tail now. Umm.. tail please?" He's usually pretty good about staying away from my feet when I am walking.

 

With Cassie, I constantly accidentally kick her or trip over her.. she's always underfoot! She'd step away, look stunned at me, then goes back under my feet.

 

If your cat doesn't spring back any time soon, I'd take her in to be checked out, as someone said, cats are good at hiding their pain.. and full weight on a paw could hurt it.