To wonder why this is so painful

[grapes2087]

On Friday I stepped on a small stone (smaller than gravel)
Hurt the expected amount initially (like stepping on a bit of Lego or similar) but since then has been getting worse and worse-really hurts to walk on it but also constantly throbbing.
How can a small thing cause so much pain and what can I do about it?! Not looking forward to work tomorrow.

Could it be embedded?

I’d bet a medical professional to take a look. Maybe a bit of glass was there too and it’s stuck?

Could it have broken a tiny bone in your foot?

No it’s definitely not embedded-it didn’t even break the skin.
can’t see any bruise but it does feel a bit swollen.

Might be worth getting it looked at, is there a minor injuries unit near you? Even a tiny amount of embedded material can cause a lot of pain and possible infection. Soft tissue injuries can be really painful though and can last a few weeks!

I’d feel like an absolute prat getting it looked as as there’s nothing to see! And I can’t see how it can have been big enough to reach a bone through my fat, hard skinned foot! It must just be a bruise but a bloody painful one!

I wonder if you broke a blood vessel, and can't see the bruising due to the hardness of the skin on your feet. I have that happen in my fingers occasionally, and it's really painful!

After initially poo poohing the idea that something was embedded inside and a month of pain I’m now thinking I can feel something under the skin-as in there’s a lump and sharp pain when I touch it in a certain way.
feel a bit stupid seeking medical intervention-and where would I go? GP? Podiatrist?

@grapes2087 the gp is your 1st port of call if they think there's something embedded in your foot they'll send you for an xray and if there's something in there you'll need a small procedure to remove it under a local anesthetic.
However I should warn you that I did something similar by stepping on a plastic handle/peg from a woden jigsaw and managed to do serious tendon damage to my foot and it didn't brake the skin or really bruise the skin but the pain and ongoing issues from it 20+ years later are ridiculous

Oh gosh poor you- that’s horrible (and worrying!) I think I will go to gp.
the pain changed from the initial throbbing to cramping type shooting pains (I wondered if this was to do with how I’d been walking to avoid it hurting) and is now more of the sharp pain I associate with a splinter.

I'd go straight to a local podiatrist if you're happy to pay. They'll get their scalpels etc and sort of your hard skin whilst they're there too. 2 birds 1 stone. Pardon the pun.