How can you tell if a cut is infected?

[Rallyaround]

This seems really pathetic, I have a fairly good tolerance for pain, but I cut my knuckle on a door latch. It bled a fair bit but all ok. That was two days ago. Tonight the pain is unreal. Is so achey and burny. My entire finger hurts up to the tip and into my hand. Not sure if it’s bruised underneath.
It doesn’t look overly red outwith the cut which I thought was a typical sign of infection. Not weeping or anything obvious. But the fact the pain is so intense is making me feel sick! I’m not usually bothered my cuts or grazes or anything. Haven’t been to the docs in a few years!

I'd go to minor injuries / walk in. It's hurting way more than you'd expect from such an injury so obviously something is wrong.

If it's hot I'd assume infection. Worth checking it out.

achey, swollen, red, oozing, hot...

Have you tried dousing it in antiseptic? Mild infections hurt less if you do that (TCP is painfree to apply)